roc/crates/compiler/builtins/bitcode/src/str.zig

2392 lines
71 KiB
Zig

const utils = @import("utils.zig");
const RocList = @import("list.zig").RocList;
const UpdateMode = utils.UpdateMode;
const std = @import("std");
const mem = std.mem;
const unicode = std.unicode;
const testing = std.testing;
const expectEqual = testing.expectEqual;
const expectError = testing.expectError;
const expect = testing.expect;
const InPlace = enum(u8) {
InPlace,
Clone,
};
const MASK_ISIZE: isize = std.math.minInt(isize);
const MASK: usize = @as(usize, @bitCast(MASK_ISIZE));
const SEAMLESS_SLICE_BIT: usize = MASK;
const SMALL_STR_MAX_LENGTH = SMALL_STRING_SIZE - 1;
const SMALL_STRING_SIZE = @sizeOf(RocStr);
fn init_blank_small_string(comptime n: usize) [n]u8 {
var prime_list: [n]u8 = undefined;
var i = 0;
while (i < n) : (i += 1) {
prime_list[i] = 0;
}
return prime_list;
}
pub const RocStr = extern struct {
bytes: ?[*]u8,
length: usize,
// For big strs, contains the capacity.
// For seamless slices contains the pointer to the original allocation.
// This pointer is to the first character of the original string.
// Note we storing an allocation pointer, the pointer must be right shifted by one.
capacity_or_alloc_ptr: usize,
pub const alignment = @alignOf(usize);
pub inline fn empty() RocStr {
return RocStr{
.length = 0,
.bytes = null,
.capacity_or_alloc_ptr = MASK,
};
}
// This clones the pointed-to bytes if they won't fit in a
// small string, and returns a (pointer, len) tuple which points to them.
pub fn init(bytes_ptr: [*]const u8, length: usize) RocStr {
var result = RocStr.allocate(length);
@memcpy(result.asU8ptrMut()[0..length], bytes_ptr[0..length]);
return result;
}
// This requires that the list is non-null.
// It also requires that start and count define a slice that does not go outside the bounds of the list.
pub fn fromSubListUnsafe(list: RocList, start: usize, count: usize, update_mode: UpdateMode) RocStr {
const start_byte = @as([*]u8, @ptrCast(list.bytes)) + start;
if (list.isSeamlessSlice()) {
return RocStr{
.bytes = start_byte,
.length = count | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = list.capacity_or_alloc_ptr & (~SEAMLESS_SLICE_BIT),
};
} else if (start == 0 and (update_mode == .InPlace or list.isUnique())) {
// Rare case, we can take over the original list.
return RocStr{
.bytes = start_byte,
.length = count,
.capacity_or_alloc_ptr = list.capacity_or_alloc_ptr, // This is guaranteed to be a proper capacity.
};
} else {
// Create seamless slice pointing to the list.
return RocStr{
.bytes = start_byte,
.length = count | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = @intFromPtr(list.bytes) >> 1,
};
}
}
pub fn isSeamlessSlice(self: RocStr) bool {
return !self.isSmallStr() and @as(isize, @bitCast(self.length)) < 0;
}
pub fn fromSlice(slice: []const u8) RocStr {
return RocStr.init(slice.ptr, slice.len);
}
fn allocateBig(length: usize, capacity: usize) RocStr {
const first_element = utils.allocateWithRefcount(capacity, @sizeOf(usize));
return RocStr{
.bytes = first_element,
.length = length,
.capacity_or_alloc_ptr = capacity,
};
}
// allocate space for a (big or small) RocStr, but put nothing in it yet.
// May have a larger capacity than the length.
pub fn allocate(length: usize) RocStr {
const element_width = 1;
const result_is_big = length >= SMALL_STRING_SIZE;
if (result_is_big) {
const capacity = utils.calculateCapacity(0, length, element_width);
return RocStr.allocateBig(length, capacity);
} else {
var string = RocStr.empty();
string.asU8ptrMut()[@sizeOf(RocStr) - 1] = @as(u8, @intCast(length)) | 0b1000_0000;
return string;
}
}
// allocate space for a (big or small) RocStr, but put nothing in it yet.
// Will have the exact same capacity as length if it is not a small string.
pub fn allocateExact(length: usize) RocStr {
const result_is_big = length >= SMALL_STRING_SIZE;
if (result_is_big) {
return RocStr.allocateBig(length, length);
} else {
var string = RocStr.empty();
string.asU8ptrMut()[@sizeOf(RocStr) - 1] = @as(u8, @intCast(length)) | 0b1000_0000;
return string;
}
}
// This returns all ones if the list is a seamless slice.
// Otherwise, it returns all zeros.
// This is done without branching for optimization purposes.
pub fn seamlessSliceMask(self: RocStr) usize {
return @as(usize, @bitCast(@as(isize, @bitCast(self.length)) >> (@bitSizeOf(isize) - 1)));
}
// returns a pointer to the original allocation.
// This pointer points to the first element of the allocation.
// The pointer is to just after the refcount.
// For big strings, it just returns their bytes pointer.
// For seamless slices, it returns the pointer stored in capacity_or_alloc_ptr.
// This does not return a valid value if the input is a small string.
pub fn getAllocationPtr(self: RocStr) ?[*]u8 {
const str_alloc_ptr = @intFromPtr(self.bytes);
const slice_alloc_ptr = self.capacity_or_alloc_ptr << 1;
const slice_mask = self.seamlessSliceMask();
const alloc_ptr = (str_alloc_ptr & ~slice_mask) | (slice_alloc_ptr & slice_mask);
return @as(?[*]u8, @ptrFromInt(alloc_ptr));
}
pub fn incref(self: RocStr, n: usize) void {
if (!self.isSmallStr()) {
const alloc_ptr = self.getAllocationPtr();
if (alloc_ptr != null) {
const isizes: [*]isize = @as([*]isize, @ptrCast(@alignCast(alloc_ptr)));
utils.increfRcPtrC(@as(*isize, @ptrCast(isizes - 1)), @as(isize, @intCast(n)));
}
}
}
pub fn decref(self: RocStr) void {
if (!self.isSmallStr()) {
utils.decref(self.getAllocationPtr(), self.capacity_or_alloc_ptr, RocStr.alignment);
}
}
pub fn eq(self: RocStr, other: RocStr) bool {
// If they are byte-for-byte equal, they're definitely equal!
if (self.bytes == other.bytes and self.length == other.length and self.capacity_or_alloc_ptr == other.capacity_or_alloc_ptr) {
return true;
}
const self_len = self.len();
const other_len = other.len();
// If their lengths are different, they're definitely unequal.
if (self_len != other_len) {
return false;
}
// Now we have to look at the string contents
const self_bytes = self.asU8ptr();
const other_bytes = other.asU8ptr();
// TODO: we can make an optimization like memcmp does in glibc.
// We can check the min shared alignment 1, 2, 4, or 8.
// Then do a copy at that alignment before falling back on one byte at a time.
// Currently we have to be unaligned because slices can be at any alignment.
var b: usize = 0;
while (b < self_len) : (b += 1) {
if (self_bytes[b] != other_bytes[b]) {
return false;
}
}
return true;
}
pub fn clone(str: RocStr) RocStr {
if (str.isSmallStr()) {
// just return the bytes
return str;
} else {
var new_str = RocStr.allocateBig(str.length, str.length);
var old_bytes: [*]u8 = @as([*]u8, @ptrCast(str.bytes));
var new_bytes: [*]u8 = @as([*]u8, @ptrCast(new_str.bytes));
@memcpy(new_bytes[0..str.length], old_bytes[0..str.length]);
return new_str;
}
}
pub fn reallocate(
self: RocStr,
new_length: usize,
) RocStr {
const element_width = 1;
const old_capacity = self.getCapacity();
if (self.isSmallStr() or self.isSeamlessSlice() or !self.isUnique()) {
return self.reallocateFresh(new_length);
}
if (self.bytes) |source_ptr| {
if (old_capacity > new_length) {
var output = self;
output.setLen(new_length);
return output;
}
const new_capacity = utils.calculateCapacity(old_capacity, new_length, element_width);
const new_source = utils.unsafeReallocate(
source_ptr,
RocStr.alignment,
old_capacity,
new_capacity,
element_width,
);
return RocStr{ .bytes = new_source, .length = new_length, .capacity_or_alloc_ptr = new_capacity };
}
return self.reallocateFresh(new_length);
}
/// reallocate by explicitly making a new allocation and copying elements over
fn reallocateFresh(
self: RocStr,
new_length: usize,
) RocStr {
const old_length = self.len();
const element_width = 1;
const result_is_big = new_length >= SMALL_STRING_SIZE;
if (result_is_big) {
const capacity = utils.calculateCapacity(0, new_length, element_width);
var result = RocStr.allocateBig(new_length, capacity);
// transfer the memory
const source_ptr = self.asU8ptr();
const dest_ptr = result.asU8ptrMut();
std.mem.copy(u8, dest_ptr[0..old_length], source_ptr[0..old_length]);
@memset(dest_ptr[old_length..new_length], 0);
self.decref();
return result;
} else {
var string = RocStr.empty();
// I believe taking this reference on the stack here is important for correctness.
// Doing it via a method call seemed to cause issues
const dest_ptr = @as([*]u8, @ptrCast(&string));
dest_ptr[@sizeOf(RocStr) - 1] = @as(u8, @intCast(new_length)) | 0b1000_0000;
const source_ptr = self.asU8ptr();
std.mem.copy(u8, dest_ptr[0..old_length], source_ptr[0..old_length]);
@memset(dest_ptr[old_length..new_length], 0);
self.decref();
return string;
}
}
pub fn isSmallStr(self: RocStr) bool {
return @as(isize, @bitCast(self.capacity_or_alloc_ptr)) < 0;
}
test "isSmallStr: returns true for empty string" {
try expect(isSmallStr(RocStr.empty()));
}
fn asArray(self: RocStr) [@sizeOf(RocStr)]u8 {
const as_ptr = @as([*]const u8, @ptrCast(&self));
const slice = as_ptr[0..@sizeOf(RocStr)];
return slice.*;
}
pub fn len(self: RocStr) usize {
if (self.isSmallStr()) {
return self.asArray()[@sizeOf(RocStr) - 1] ^ 0b1000_0000;
} else {
return self.length & (~SEAMLESS_SLICE_BIT);
}
}
pub fn setLen(self: *RocStr, length: usize) void {
if (self.isSmallStr()) {
self.asU8ptrMut()[@sizeOf(RocStr) - 1] = @as(u8, @intCast(length)) | 0b1000_0000;
} else {
self.length = length | (SEAMLESS_SLICE_BIT & self.length);
}
}
pub fn getCapacity(self: RocStr) usize {
if (self.isSmallStr()) {
return SMALL_STR_MAX_LENGTH;
} else if (self.isSeamlessSlice()) {
return self.length & (~SEAMLESS_SLICE_BIT);
} else {
return self.capacity_or_alloc_ptr;
}
}
// This does a small string check, but no bounds checking whatsoever!
pub fn getUnchecked(self: RocStr, index: usize) u8 {
if (self.isSmallStr()) {
return self.asArray()[index];
} else {
const bytes = self.bytes orelse unreachable;
return bytes[index];
}
}
pub fn isEmpty(self: RocStr) bool {
return self.len() == 0;
}
pub fn isUnique(self: RocStr) bool {
// small strings can be copied
if (self.isSmallStr()) {
return true;
}
// otherwise, check if the refcount is one
return @call(.always_inline, RocStr.isRefcountOne, .{self});
}
fn isRefcountOne(self: RocStr) bool {
return self.refcountMachine() == utils.REFCOUNT_ONE;
}
fn refcountMachine(self: RocStr) usize {
if ((self.getCapacity() == 0 and !self.isSeamlessSlice()) or self.isSmallStr()) {
return utils.REFCOUNT_ONE;
}
const ptr: [*]usize = @as([*]usize, @ptrCast(@alignCast(self.bytes)));
return (ptr - 1)[0];
}
fn refcountHuman(self: RocStr) usize {
return self.refcountMachine() - utils.REFCOUNT_ONE + 1;
}
pub fn asSlice(self: *const RocStr) []const u8 {
return self.asU8ptr()[0..self.len()];
}
pub fn asSliceWithCapacity(self: *const RocStr) []const u8 {
return self.asU8ptr()[0..self.getCapacity()];
}
pub fn asSliceWithCapacityMut(self: *RocStr) []u8 {
return self.asU8ptrMut()[0..self.getCapacity()];
}
pub fn asU8ptr(self: *const RocStr) [*]const u8 {
if (self.isSmallStr()) {
return @as([*]const u8, @ptrCast(self));
} else {
return @as([*]const u8, @ptrCast(self.bytes));
}
}
pub fn asU8ptrMut(self: *RocStr) [*]u8 {
if (self.isSmallStr()) {
return @as([*]u8, @ptrCast(self));
} else {
return @as([*]u8, @ptrCast(self.bytes));
}
}
// Given a pointer to some bytes, write the first (len) bytes of this
// RocStr's contents into it.
//
// One use for this function is writing into an `alloca` for a C string that
// only needs to live long enough to be passed as an argument to
// a C function - like the file path argument to `fopen`.
pub fn memcpy(self: RocStr, dest: [*]u8) void {
const src = self.asU8ptr();
@memcpy(dest[0..self.len()], src[0..self.len()]);
}
test "RocStr.eq: small, equal" {
const str1_len = 3;
var str1: [str1_len]u8 = "abc".*;
const str1_ptr: [*]u8 = &str1;
var roc_str1 = RocStr.init(str1_ptr, str1_len);
const str2_len = 3;
var str2: [str2_len]u8 = "abc".*;
const str2_ptr: [*]u8 = &str2;
var roc_str2 = RocStr.init(str2_ptr, str2_len);
try expect(roc_str1.eq(roc_str2));
roc_str1.decref();
roc_str2.decref();
}
test "RocStr.eq: small, not equal, different length" {
const str1_len = 4;
var str1: [str1_len]u8 = "abcd".*;
const str1_ptr: [*]u8 = &str1;
var roc_str1 = RocStr.init(str1_ptr, str1_len);
const str2_len = 3;
var str2: [str2_len]u8 = "abc".*;
const str2_ptr: [*]u8 = &str2;
var roc_str2 = RocStr.init(str2_ptr, str2_len);
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(!roc_str1.eq(roc_str2));
}
test "RocStr.eq: small, not equal, same length" {
const str1_len = 3;
var str1: [str1_len]u8 = "acb".*;
const str1_ptr: [*]u8 = &str1;
var roc_str1 = RocStr.init(str1_ptr, str1_len);
const str2_len = 3;
var str2: [str2_len]u8 = "abc".*;
const str2_ptr: [*]u8 = &str2;
var roc_str2 = RocStr.init(str2_ptr, str2_len);
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(!roc_str1.eq(roc_str2));
}
test "RocStr.eq: large, equal" {
const content = "012345678901234567890123456789";
const roc_str1 = RocStr.init(content, content.len);
const roc_str2 = RocStr.init(content, content.len);
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(roc_str1.eq(roc_str2));
}
test "RocStr.eq: large, different lengths, unequal" {
const content1 = "012345678901234567890123456789";
const roc_str1 = RocStr.init(content1, content1.len);
const content2 = "012345678901234567890";
const roc_str2 = RocStr.init(content2, content2.len);
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(!roc_str1.eq(roc_str2));
}
test "RocStr.eq: large, different content, unequal" {
const content1 = "012345678901234567890123456789!!";
const roc_str1 = RocStr.init(content1, content1.len);
const content2 = "012345678901234567890123456789--";
const roc_str2 = RocStr.init(content2, content2.len);
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(!roc_str1.eq(roc_str2));
}
test "RocStr.eq: large, garbage after end, equal" {
const content = "012345678901234567890123456789";
const roc_str1 = RocStr.init(content, content.len);
const roc_str2 = RocStr.init(content, content.len);
try expect(roc_str1.bytes != roc_str2.bytes);
// Insert garbage after the end of each string
roc_str1.bytes.?[30] = '!';
roc_str1.bytes.?[31] = '!';
roc_str2.bytes.?[30] = '-';
roc_str2.bytes.?[31] = '-';
defer {
roc_str1.decref();
roc_str2.decref();
}
try expect(roc_str1.eq(roc_str2));
}
};
pub fn init(bytes_ptr: [*]const u8, length: usize) callconv(.C) RocStr {
return @call(.always_inline, RocStr.init, .{ bytes_ptr, length });
}
// Str.equal
pub fn strEqual(self: RocStr, other: RocStr) callconv(.C) bool {
return self.eq(other);
}
// Str.numberOfBytes
pub fn strNumberOfBytes(string: RocStr) callconv(.C) usize {
return string.len();
}
// Str.fromInt
pub fn exportFromInt(comptime T: type, comptime name: []const u8) void {
comptime var f = struct {
fn func(int: T) callconv(.C) RocStr {
return @call(.always_inline, strFromIntHelp, .{ T, int });
}
}.func;
@export(f, .{ .name = name ++ @typeName(T), .linkage = .Strong });
}
fn strFromIntHelp(comptime T: type, int: T) RocStr {
// determine maximum size for this T
const size = comptime blk: {
// the string representation of the minimum i128 value uses at most 40 characters
var buf: [40]u8 = undefined;
var resultMin = std.fmt.bufPrint(&buf, "{}", .{std.math.minInt(T)}) catch unreachable;
var resultMax = std.fmt.bufPrint(&buf, "{}", .{std.math.maxInt(T)}) catch unreachable;
var result = if (resultMin.len > resultMax.len) resultMin.len else resultMax.len;
break :blk result;
};
var buf: [size]u8 = undefined;
const result = std.fmt.bufPrint(&buf, "{}", .{int}) catch unreachable;
return RocStr.init(&buf, result.len);
}
// Str.fromFloat
pub fn exportFromFloat(comptime T: type, comptime name: []const u8) void {
comptime var f = struct {
fn func(float: T) callconv(.C) RocStr {
return @call(.always_inline, strFromFloatHelp, .{ T, float });
}
}.func;
@export(f, .{ .name = name ++ @typeName(T), .linkage = .Strong });
}
fn strFromFloatHelp(comptime T: type, float: T) RocStr {
var buf: [400]u8 = undefined;
const result = std.fmt.bufPrint(&buf, "{d}", .{float}) catch unreachable;
return RocStr.init(&buf, result.len);
}
// Str.split
pub fn strSplit(string: RocStr, delimiter: RocStr) callconv(.C) RocList {
const segment_count = countSegments(string, delimiter);
const list = RocList.allocate(@alignOf(RocStr), segment_count, @sizeOf(RocStr));
if (list.bytes) |bytes| {
const strings = @as([*]RocStr, @ptrCast(@alignCast(bytes)));
strSplitHelp(strings, string, delimiter);
}
return list;
}
fn initFromSmallStr(slice_bytes: [*]u8, len: usize, _: usize) RocStr {
return RocStr.init(slice_bytes, len);
}
// The alloc_ptr must already be shifted to be ready for storing in a seamless slice.
fn initFromBigStr(slice_bytes: [*]u8, len: usize, alloc_ptr: usize) RocStr {
// Here we can make seamless slices instead of copying to a new small str.
return RocStr{
.bytes = slice_bytes,
.length = len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = alloc_ptr,
};
}
fn strSplitHelp(array: [*]RocStr, string: RocStr, delimiter: RocStr) void {
if (delimiter.len() == 0) {
string.incref(1);
array[0] = string;
return;
}
var it = std.mem.split(u8, string.asSlice(), delimiter.asSlice());
var i: usize = 0;
var offset: usize = 0;
while (it.next()) |zig_slice| {
const roc_slice = substringUnsafe(string, offset, zig_slice.len);
array[i] = roc_slice;
i += 1;
offset += zig_slice.len + delimiter.len();
}
// Correct refcount for all of the splits made.
string.incref(i); // i == array.len()
}
test "strSplitHelp: empty delimiter" {
// Str.split "abc" "" == ["abc"]
const str_arr = "abc";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
var array: [1]RocStr = undefined;
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
var expected = [1]RocStr{
str,
};
defer {
for (array) |roc_str| {
roc_str.decref();
}
for (expected) |roc_str| {
roc_str.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
}
test "strSplitHelp: no delimiter" {
// Str.split "abc" "!" == ["abc"]
const str_arr = "abc";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "!";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
var array: [1]RocStr = undefined;
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
var expected = [1]RocStr{
str,
};
defer {
for (array) |roc_str| {
roc_str.decref();
}
for (expected) |roc_str| {
roc_str.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
}
test "strSplitHelp: empty start" {
const str_arr = "/a";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "/";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
const array_len: usize = 2;
var array: [array_len]RocStr = [_]RocStr{
undefined,
undefined,
};
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
const one = RocStr.init("a", 1);
var expected = [2]RocStr{
RocStr.empty(), one,
};
defer {
for (array) |rocStr| {
rocStr.decref();
}
for (expected) |rocStr| {
rocStr.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
}
test "strSplitHelp: empty end" {
const str_arr = "1---- ---- ---- ---- ----2---- ---- ---- ---- ----";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "---- ---- ---- ---- ----";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
const array_len: usize = 3;
var array: [array_len]RocStr = [_]RocStr{
undefined,
undefined,
undefined,
};
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
const one = RocStr.init("1", 1);
const two = RocStr.init("2", 1);
var expected = [3]RocStr{
one, two, RocStr.empty(),
};
defer {
for (array) |rocStr| {
rocStr.decref();
}
for (expected) |rocStr| {
rocStr.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
try expect(array[2].eq(expected[2]));
}
test "strSplitHelp: string equals delimiter" {
const str_delimiter_arr = "/";
const str_delimiter = RocStr.init(str_delimiter_arr, str_delimiter_arr.len);
const array_len: usize = 2;
var array: [array_len]RocStr = [_]RocStr{
undefined,
undefined,
};
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str_delimiter, str_delimiter);
var expected = [2]RocStr{ RocStr.empty(), RocStr.empty() };
defer {
for (array) |rocStr| {
rocStr.decref();
}
for (expected) |rocStr| {
rocStr.decref();
}
str_delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
}
test "strSplitHelp: delimiter on sides" {
const str_arr = "tttghittt";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "ttt";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
const array_len: usize = 3;
var array: [array_len]RocStr = [_]RocStr{
undefined,
undefined,
undefined,
};
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
const ghi_arr = "ghi";
const ghi = RocStr.init(ghi_arr, ghi_arr.len);
var expected = [3]RocStr{
RocStr.empty(), ghi, RocStr.empty(),
};
defer {
for (array) |rocStr| {
rocStr.decref();
}
for (expected) |rocStr| {
rocStr.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
try expect(array[2].eq(expected[2]));
}
test "strSplitHelp: three pieces" {
// Str.split "a!b!c" "!" == ["a", "b", "c"]
const str_arr = "a!b!c";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "!";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
const array_len: usize = 3;
var array: [array_len]RocStr = undefined;
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
const a = RocStr.init("a", 1);
const b = RocStr.init("b", 1);
const c = RocStr.init("c", 1);
var expected_array = [array_len]RocStr{
a, b, c,
};
defer {
for (array) |roc_str| {
roc_str.decref();
}
for (expected_array) |roc_str| {
roc_str.decref();
}
str.decref();
delimiter.decref();
}
try expectEqual(expected_array.len, array.len);
try expect(array[0].eq(expected_array[0]));
try expect(array[1].eq(expected_array[1]));
try expect(array[2].eq(expected_array[2]));
}
test "strSplitHelp: overlapping delimiter 1" {
// Str.split "aaa" "aa" == ["", "a"]
const str_arr = "aaa";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "aa";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
var array: [2]RocStr = undefined;
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
var expected = [2]RocStr{
RocStr.empty(),
RocStr.init("a", 1),
};
// strings are all small so we ignore freeing the memory
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
}
test "strSplitHelp: overlapping delimiter 2" {
// Str.split "aaa" "aa" == ["", "a"]
const str_arr = "aaaa";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "aa";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
var array: [3]RocStr = undefined;
const array_ptr: [*]RocStr = &array;
strSplitHelp(array_ptr, str, delimiter);
var expected = [3]RocStr{
RocStr.empty(),
RocStr.empty(),
RocStr.empty(),
};
// strings are all small so we ignore freeing the memory
try expectEqual(array.len, expected.len);
try expect(array[0].eq(expected[0]));
try expect(array[1].eq(expected[1]));
try expect(array[2].eq(expected[2]));
}
// This is used for `Str.split : Str, Str -> Array Str
// It is used to count how many segments the input `_str`
// needs to be broken into, so that we can allocate a array
// of that size. It always returns at least 1.
pub fn countSegments(string: RocStr, delimiter: RocStr) callconv(.C) usize {
if (delimiter.isEmpty()) {
return 1;
}
var it = std.mem.split(u8, string.asSlice(), delimiter.asSlice());
var count: usize = 0;
while (it.next()) |_| : (count += 1) {}
return count;
}
test "countSegments: long delimiter" {
// Str.split "str" "delimiter" == ["str"]
// 1 segment
const str_arr = "str";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "delimiter";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
defer {
str.decref();
delimiter.decref();
}
const segments_count = countSegments(str, delimiter);
try expectEqual(segments_count, 1);
}
test "countSegments: delimiter at start" {
// Str.split "hello there" "hello" == ["", " there"]
// 2 segments
const str_arr = "hello there";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "hello";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
defer {
str.decref();
delimiter.decref();
}
const segments_count = countSegments(str, delimiter);
try expectEqual(segments_count, 2);
}
test "countSegments: delimiter interspered" {
// Str.split "a!b!c" "!" == ["a", "b", "c"]
// 3 segments
const str_arr = "a!b!c";
const str = RocStr.init(str_arr, str_arr.len);
const delimiter_arr = "!";
const delimiter = RocStr.init(delimiter_arr, delimiter_arr.len);
defer {
str.decref();
delimiter.decref();
}
const segments_count = countSegments(str, delimiter);
try expectEqual(segments_count, 3);
}
test "countSegments: string equals delimiter" {
// Str.split "/" "/" == ["", ""]
// 2 segments
const str_delimiter_arr = "/";
const str_delimiter = RocStr.init(str_delimiter_arr, str_delimiter_arr.len);
defer {
str_delimiter.decref();
}
const segments_count = countSegments(str_delimiter, str_delimiter);
try expectEqual(segments_count, 2);
}
test "countSegments: overlapping delimiter 1" {
// Str.split "aaa" "aa" == ["", "a"]
const segments_count = countSegments(RocStr.init("aaa", 3), RocStr.init("aa", 2));
try expectEqual(segments_count, 2);
}
test "countSegments: overlapping delimiter 2" {
// Str.split "aaa" "aa" == ["", "a"]
const segments_count = countSegments(RocStr.init("aaaa", 4), RocStr.init("aa", 2));
try expectEqual(segments_count, 3);
}
pub fn countUtf8Bytes(string: RocStr) callconv(.C) u64 {
return @intCast(string.len());
}
pub fn isEmpty(string: RocStr) callconv(.C) bool {
return string.isEmpty();
}
pub fn getCapacity(string: RocStr) callconv(.C) usize {
return string.getCapacity();
}
pub fn substringUnsafeC(string: RocStr, start_u64: u64, length_u64: u64) callconv(.C) RocStr {
const start: usize = @intCast(start_u64);
const length: usize = @intCast(length_u64);
return substringUnsafe(string, start, length);
}
fn substringUnsafe(string: RocStr, start: usize, length: usize) RocStr {
if (string.isSmallStr()) {
if (start == 0) {
var output = string;
output.setLen(length);
return output;
}
const slice = string.asSlice()[start .. start + length];
return RocStr.fromSlice(slice);
}
if (string.bytes) |source_ptr| {
if (start == 0 and string.isUnique()) {
var output = string;
output.setLen(length);
return output;
} else {
// Shifting right by 1 is required to avoid the highest bit of capacity being set.
// If it was set, the slice would get interpreted as a small string.
const str_alloc_ptr = (@intFromPtr(source_ptr) >> 1);
const slice_alloc_ptr = string.capacity_or_alloc_ptr;
const slice_mask = string.seamlessSliceMask();
const alloc_ptr = (str_alloc_ptr & ~slice_mask) | (slice_alloc_ptr & slice_mask);
return RocStr{
.bytes = source_ptr + start,
.length = length | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = alloc_ptr,
};
}
}
return RocStr.empty();
}
pub fn getUnsafeC(string: RocStr, index: u64) callconv(.C) u8 {
return string.getUnchecked(@intCast(index));
}
test "substringUnsafe: start" {
const str = RocStr.fromSlice("abcdef");
defer str.decref();
const expected = RocStr.fromSlice("abc");
defer expected.decref();
const actual = substringUnsafe(str, 0, 3);
try expect(RocStr.eq(actual, expected));
}
test "substringUnsafe: middle" {
const str = RocStr.fromSlice("abcdef");
defer str.decref();
const expected = RocStr.fromSlice("bcd");
defer expected.decref();
const actual = substringUnsafe(str, 1, 3);
try expect(RocStr.eq(actual, expected));
}
test "substringUnsafe: end" {
const str = RocStr.fromSlice("a string so long it is heap-allocated");
defer str.decref();
const expected = RocStr.fromSlice("heap-allocated");
defer expected.decref();
const actual = substringUnsafe(str, 23, 37 - 23);
try expect(RocStr.eq(actual, expected));
}
// Str.startsWith
pub fn startsWith(string: RocStr, prefix: RocStr) callconv(.C) bool {
const bytes_len = string.len();
const bytes_ptr = string.asU8ptr();
const prefix_len = prefix.len();
const prefix_ptr = prefix.asU8ptr();
if (prefix_len > bytes_len) {
return false;
}
// we won't exceed bytes_len due to the previous check
var i: usize = 0;
while (i < prefix_len) {
if (bytes_ptr[i] != prefix_ptr[i]) {
return false;
}
i += 1;
}
return true;
}
// Str.repeat
pub fn repeatC(string: RocStr, count_u64: u64) callconv(.C) RocStr {
const count: usize = @intCast(count_u64);
const bytes_len = string.len();
const bytes_ptr = string.asU8ptr();
var ret_string = RocStr.allocate(count * bytes_len);
var ret_string_ptr = ret_string.asU8ptrMut();
var i: usize = 0;
while (i < count) : (i += 1) {
@memcpy(ret_string_ptr[0..bytes_len], bytes_ptr[0..bytes_len]);
ret_string_ptr += bytes_len;
}
return ret_string;
}
test "startsWith: foo starts with fo" {
const foo = RocStr.fromSlice("foo");
const fo = RocStr.fromSlice("fo");
try expect(startsWith(foo, fo));
}
test "startsWith: 123456789123456789 starts with 123456789123456789" {
const str = RocStr.fromSlice("123456789123456789");
defer str.decref();
try expect(startsWith(str, str));
}
test "startsWith: 12345678912345678910 starts with 123456789123456789" {
const str = RocStr.fromSlice("12345678912345678910");
defer str.decref();
const prefix = RocStr.fromSlice("123456789123456789");
defer prefix.decref();
try expect(startsWith(str, prefix));
}
// Str.endsWith
pub fn endsWith(string: RocStr, suffix: RocStr) callconv(.C) bool {
const bytes_len = string.len();
const bytes_ptr = string.asU8ptr();
const suffix_len = suffix.len();
const suffix_ptr = suffix.asU8ptr();
if (suffix_len > bytes_len) {
return false;
}
const offset: usize = bytes_len - suffix_len;
var i: usize = 0;
while (i < suffix_len) {
if (bytes_ptr[i + offset] != suffix_ptr[i]) {
return false;
}
i += 1;
}
return true;
}
test "endsWith: foo ends with oo" {
const foo = RocStr.init("foo", 3);
const oo = RocStr.init("oo", 2);
defer foo.decref();
defer oo.decref();
try expect(endsWith(foo, oo));
}
test "endsWith: 123456789123456789 ends with 123456789123456789" {
const str = RocStr.init("123456789123456789", 18);
defer str.decref();
try expect(endsWith(str, str));
}
test "endsWith: 12345678912345678910 ends with 345678912345678910" {
const str = RocStr.init("12345678912345678910", 20);
const suffix = RocStr.init("345678912345678910", 18);
defer str.decref();
defer suffix.decref();
try expect(endsWith(str, suffix));
}
test "endsWith: hello world ends with world" {
const str = RocStr.init("hello world", 11);
const suffix = RocStr.init("world", 5);
defer str.decref();
defer suffix.decref();
try expect(endsWith(str, suffix));
}
// Str.concat
pub fn strConcatC(arg1: RocStr, arg2: RocStr) callconv(.C) RocStr {
return @call(.always_inline, strConcat, .{ arg1, arg2 });
}
fn strConcat(arg1: RocStr, arg2: RocStr) RocStr {
// NOTE: we don't special-case the first argument being empty. That is because it is owned and
// may have sufficient capacity to store the rest of the list.
if (arg2.isEmpty()) {
// the first argument is owned, so we can return it without cloning
return arg1;
} else {
const combined_length = arg1.len() + arg2.len();
var result = arg1.reallocate(combined_length);
@memcpy(result.asU8ptrMut()[arg1.len()..combined_length], arg2.asU8ptr()[0..arg2.len()]);
return result;
}
}
test "RocStr.concat: small concat small" {
const str1_len = 3;
var str1: [str1_len]u8 = "foo".*;
const str1_ptr: [*]u8 = &str1;
var roc_str1 = RocStr.init(str1_ptr, str1_len);
const str2_len = 3;
var str2: [str2_len]u8 = "abc".*;
const str2_ptr: [*]u8 = &str2;
var roc_str2 = RocStr.init(str2_ptr, str2_len);
const str3_len = 6;
var str3: [str3_len]u8 = "fooabc".*;
const str3_ptr: [*]u8 = &str3;
var roc_str3 = RocStr.init(str3_ptr, str3_len);
defer {
roc_str1.decref();
roc_str2.decref();
roc_str3.decref();
}
const result = strConcat(roc_str1, roc_str2);
defer result.decref();
try expect(roc_str3.eq(result));
}
pub const RocListStr = extern struct {
list_elements: ?[*]RocStr,
list_length: usize,
list_capacity_or_alloc_ptr: usize,
};
// Str.joinWith
pub fn strJoinWithC(list: RocList, separator: RocStr) callconv(.C) RocStr {
const roc_list_str = RocListStr{
.list_elements = @as(?[*]RocStr, @ptrCast(@alignCast(list.bytes))),
.list_length = list.length,
.list_capacity_or_alloc_ptr = list.capacity_or_alloc_ptr,
};
return @call(.always_inline, strJoinWith, .{ roc_list_str, separator });
}
fn strJoinWith(list: RocListStr, separator: RocStr) RocStr {
const len = list.list_length;
if (len == 0) {
return RocStr.empty();
} else {
const ptr = @as([*]RocStr, @ptrCast(list.list_elements));
const slice: []RocStr = ptr[0..len];
// determine the size of the result
var total_size: usize = 0;
for (slice) |substr| {
total_size += substr.len();
}
// include size of the separator
total_size += separator.len() * (len - 1);
var result = RocStr.allocate(total_size);
var result_ptr = result.asU8ptrMut();
var offset: usize = 0;
for (slice[0 .. len - 1]) |substr| {
substr.memcpy(result_ptr + offset);
offset += substr.len();
separator.memcpy(result_ptr + offset);
offset += separator.len();
}
const substr = slice[len - 1];
substr.memcpy(result_ptr + offset);
return result;
}
}
test "RocStr.joinWith: result is big" {
const sep_len = 2;
var sep: [sep_len]u8 = ", ".*;
const sep_ptr: [*]u8 = &sep;
var roc_sep = RocStr.init(sep_ptr, sep_len);
const elem_len = 13;
var elem: [elem_len]u8 = "foobarbazspam".*;
const elem_ptr: [*]u8 = &elem;
var roc_elem = RocStr.init(elem_ptr, elem_len);
const result_len = 43;
var xresult: [result_len]u8 = "foobarbazspam, foobarbazspam, foobarbazspam".*;
const result_ptr: [*]u8 = &xresult;
var roc_result = RocStr.init(result_ptr, result_len);
var elements: [3]RocStr = .{ roc_elem, roc_elem, roc_elem };
const list = RocListStr{
.list_length = 3,
.list_capacity_or_alloc_ptr = 3,
.list_elements = @as([*]RocStr, @ptrCast(&elements)),
};
defer {
roc_sep.decref();
roc_elem.decref();
roc_result.decref();
}
const result = strJoinWith(list, roc_sep);
defer result.decref();
try expect(roc_result.eq(result));
}
// Str.toUtf8
pub fn strToUtf8C(arg: RocStr) callconv(.C) RocList {
return strToBytes(arg);
}
inline fn strToBytes(arg: RocStr) RocList {
const length = arg.len();
if (length == 0) {
return RocList.empty();
} else if (arg.isSmallStr()) {
const ptr = utils.allocateWithRefcount(length, RocStr.alignment);
@memcpy(ptr[0..length], arg.asU8ptr()[0..length]);
return RocList{ .length = length, .bytes = ptr, .capacity_or_alloc_ptr = length };
} else {
const is_seamless_slice = arg.length & SEAMLESS_SLICE_BIT;
return RocList{ .length = length, .bytes = arg.bytes, .capacity_or_alloc_ptr = arg.capacity_or_alloc_ptr | is_seamless_slice };
}
}
const FromUtf8Result = extern struct {
byte_index: u64,
string: RocStr,
is_ok: bool,
problem_code: Utf8ByteProblem,
};
pub fn fromUtf8C(
list: RocList,
update_mode: UpdateMode,
) callconv(.C) FromUtf8Result {
return fromUtf8(list, update_mode);
}
pub fn fromUtf8(
list: RocList,
update_mode: UpdateMode,
) FromUtf8Result {
if (list.len() == 0) {
list.decref(1); // Alignment 1 for List U8
return FromUtf8Result{
.is_ok = true,
.string = RocStr.empty(),
.byte_index = 0,
.problem_code = Utf8ByteProblem.InvalidStartByte,
};
}
const bytes = @as([*]const u8, @ptrCast(list.bytes))[0..list.len()];
if (isValidUnicode(bytes)) {
// Make a seamless slice of the input.
const string = RocStr.fromSubListUnsafe(list, 0, list.len(), update_mode);
return FromUtf8Result{
.is_ok = true,
.string = string,
.byte_index = 0,
.problem_code = Utf8ByteProblem.InvalidStartByte,
};
} else {
const temp = errorToProblem(bytes);
list.decref(1); // Alignment 1 for List U8
return FromUtf8Result{
.is_ok = false,
.string = RocStr.empty(),
.byte_index = @intCast(temp.index),
.problem_code = temp.problem,
};
}
}
fn errorToProblem(bytes: []const u8) struct { index: usize, problem: Utf8ByteProblem } {
const len = bytes.len;
var index: usize = 0;
while (index < len) {
const nextNumBytes = numberOfNextCodepointBytes(bytes, index) catch |err| {
switch (err) {
error.UnexpectedEof => {
return .{ .index = index, .problem = Utf8ByteProblem.UnexpectedEndOfSequence };
},
error.Utf8InvalidStartByte => return .{ .index = index, .problem = Utf8ByteProblem.InvalidStartByte },
error.Utf8ExpectedContinuation => return .{ .index = index, .problem = Utf8ByteProblem.ExpectedContinuation },
error.Utf8OverlongEncoding => return .{ .index = index, .problem = Utf8ByteProblem.OverlongEncoding },
error.Utf8EncodesSurrogateHalf => return .{ .index = index, .problem = Utf8ByteProblem.EncodesSurrogateHalf },
error.Utf8CodepointTooLarge => return .{ .index = index, .problem = Utf8ByteProblem.CodepointTooLarge },
}
};
index += nextNumBytes;
}
unreachable;
}
pub fn isValidUnicode(buf: []const u8) bool {
const size = @sizeOf(u64);
// TODO: we should test changing the step on other platforms.
// The general tradeoff is making extremely large strings potentially much faster
// at the cost of small strings being slightly slower.
const step = size;
var i: usize = 0;
while (i + step < buf.len) {
var bytes: u64 = undefined;
@memcpy(@as([*]u8, @ptrCast(&bytes))[0..size], buf[i..(i + size)]);
const unicode_bytes = bytes & 0x8080_8080_8080_8080;
if (unicode_bytes == 0) {
i += step;
continue;
}
while (buf[i] < 0b1000_0000) : (i += 1) {}
while (buf[i] >= 0b1000_0000) {
// This forces prefetching, otherwise the loop can run at about half speed.
if (i + 4 >= buf.len) break;
var small_buf: [4]u8 = undefined;
@memcpy(small_buf[0..4], buf[i..(i + 4)]);
// TODO: Should we always inline these function calls below?
if (std.unicode.utf8ByteSequenceLength(small_buf[0])) |cp_len| {
if (std.meta.isError(std.unicode.utf8Decode(small_buf[0..cp_len]))) {
return false;
}
i += cp_len;
} else |_| {
return false;
}
}
}
if (i == buf.len) return true;
while (buf[i] < 0b1000_0000) {
i += 1;
if (i == buf.len) return true;
}
return @call(.always_inline, unicode.utf8ValidateSlice, .{buf[i..]});
}
const Utf8DecodeError = error{
UnexpectedEof,
Utf8InvalidStartByte,
Utf8ExpectedContinuation,
Utf8OverlongEncoding,
Utf8EncodesSurrogateHalf,
Utf8CodepointTooLarge,
};
// Essentially unicode.utf8ValidateSlice -> https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L156
// but only for the next codepoint from the index. Then we return the number of bytes of that codepoint.
// TODO: we only ever use the values 0-4, so can we use smaller int than `usize`?
pub fn numberOfNextCodepointBytes(bytes: []const u8, index: usize) Utf8DecodeError!usize {
const codepoint_len = try unicode.utf8ByteSequenceLength(bytes[index]);
const codepoint_end_index = index + codepoint_len;
if (codepoint_end_index > bytes.len) {
return error.UnexpectedEof;
}
_ = try unicode.utf8Decode(bytes[index..codepoint_end_index]);
return codepoint_end_index - index;
}
// Return types for validateUtf8Bytes
// Values must be in alphabetical order. That is, lowest values are the first alphabetically.
pub const Utf8ByteProblem = enum(u8) {
CodepointTooLarge = 0,
EncodesSurrogateHalf = 1,
ExpectedContinuation = 2,
InvalidStartByte = 3,
OverlongEncoding = 4,
UnexpectedEndOfSequence = 5,
};
fn validateUtf8Bytes(bytes: [*]u8, length: usize) FromUtf8Result {
return fromUtf8(RocList{ .bytes = bytes, .length = length, .capacity_or_alloc_ptr = length }, .Immutable);
}
fn validateUtf8BytesX(str: RocList) FromUtf8Result {
return fromUtf8(str, .Immutable);
}
fn expectOk(result: FromUtf8Result) !void {
try expectEqual(result.is_ok, true);
}
fn sliceHelp(bytes: [*]const u8, length: usize) RocList {
var list = RocList.allocate(RocStr.alignment, length, @sizeOf(u8));
var list_bytes = list.bytes orelse unreachable;
@memcpy(list_bytes[0..length], bytes[0..length]);
list.length = length;
return list;
}
fn toErrUtf8ByteResponse(index: usize, problem: Utf8ByteProblem) FromUtf8Result {
return FromUtf8Result{ .is_ok = false, .string = RocStr.empty(), .byte_index = @as(u64, @intCast(index)), .problem_code = problem };
}
// NOTE on memory: the validate function consumes a RC token of the input. Since
// we freshly created it (in `sliceHelp`), it has only one RC token, and input list will be deallocated.
//
// If we tested with big strings, we'd have to deallocate the output string, but never the input list
test "validateUtf8Bytes: ascii" {
const raw = "abc";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
const str_result = validateUtf8BytesX(list);
defer str_result.string.decref();
try expectOk(str_result);
}
test "validateUtf8Bytes: unicode œ" {
const raw = "œ";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
const str_result = validateUtf8BytesX(list);
defer str_result.string.decref();
try expectOk(str_result);
}
test "validateUtf8Bytes: unicode ∆" {
const raw = "";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
const str_result = validateUtf8BytesX(list);
defer str_result.string.decref();
try expectOk(str_result);
}
test "validateUtf8Bytes: emoji" {
const raw = "💖";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
const str_result = validateUtf8BytesX(list);
defer str_result.string.decref();
try expectOk(str_result);
}
test "validateUtf8Bytes: unicode ∆ in middle of array" {
const raw = "œb∆c¬";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
const str_result = validateUtf8BytesX(list);
defer str_result.string.decref();
try expectOk(str_result);
}
fn expectErr(list: RocList, index: usize, err: Utf8DecodeError, problem: Utf8ByteProblem) !void {
const str_ptr = @as([*]u8, @ptrCast(list.bytes));
const len = list.length;
try expectError(err, numberOfNextCodepointBytes(str_ptr[0..len], index));
try expectEqual(toErrUtf8ByteResponse(index, problem), validateUtf8Bytes(str_ptr, len));
}
test "validateUtf8Bytes: invalid start byte" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L426
const raw = "ab\x80c";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 2, error.Utf8InvalidStartByte, Utf8ByteProblem.InvalidStartByte);
}
test "validateUtf8Bytes: unexpected eof for 2 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L426
const raw = "abc\xc2";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.UnexpectedEof, Utf8ByteProblem.UnexpectedEndOfSequence);
}
test "validateUtf8Bytes: expected continuation for 2 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L426
const raw = "abc\xc2\x00";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8ExpectedContinuation, Utf8ByteProblem.ExpectedContinuation);
}
test "validateUtf8Bytes: unexpected eof for 3 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L430
const raw = "abc\xe0\x00";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.UnexpectedEof, Utf8ByteProblem.UnexpectedEndOfSequence);
}
test "validateUtf8Bytes: expected continuation for 3 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L430
const raw = "abc\xe0\xa0\xc0";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8ExpectedContinuation, Utf8ByteProblem.ExpectedContinuation);
}
test "validateUtf8Bytes: unexpected eof for 4 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L437
const raw = "abc\xf0\x90\x00";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.UnexpectedEof, Utf8ByteProblem.UnexpectedEndOfSequence);
}
test "validateUtf8Bytes: expected continuation for 4 byte sequence" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L437
const raw = "abc\xf0\x90\x80\x00";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8ExpectedContinuation, Utf8ByteProblem.ExpectedContinuation);
}
test "validateUtf8Bytes: overlong" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L451
const raw = "abc\xf0\x80\x80\x80";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8OverlongEncoding, Utf8ByteProblem.OverlongEncoding);
}
test "validateUtf8Bytes: codepoint out too large" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L465
const raw = "abc\xf4\x90\x80\x80";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8CodepointTooLarge, Utf8ByteProblem.CodepointTooLarge);
}
test "validateUtf8Bytes: surrogate halves" {
// https://github.com/ziglang/zig/blob/0.7.x/lib/std/unicode.zig#L468
const raw = "abc\xed\xa0\x80";
const ptr: [*]const u8 = @as([*]const u8, @ptrCast(raw));
const list = sliceHelp(ptr, raw.len);
try expectErr(list, 3, error.Utf8EncodesSurrogateHalf, Utf8ByteProblem.EncodesSurrogateHalf);
}
fn isWhitespace(codepoint: u21) bool {
// https://www.unicode.org/Public/UCD/latest/ucd/PropList.txt
return switch (codepoint) {
0x0009...0x000D => true, // control characters
0x0020 => true, // space
0x0085 => true, // control character
0x00A0 => true, // no-break space
0x1680 => true, // ogham space
0x2000...0x200A => true, // en quad..hair space
0x200E...0x200F => true, // left-to-right & right-to-left marks
0x2028 => true, // line separator
0x2029 => true, // paragraph separator
0x202F => true, // narrow no-break space
0x205F => true, // medium mathematical space
0x3000 => true, // ideographic space
else => false,
};
}
test "isWhitespace" {
try expect(isWhitespace(' '));
try expect(isWhitespace('\u{00A0}'));
try expect(!isWhitespace('x'));
}
pub fn strTrim(input_string: RocStr) callconv(.C) RocStr {
var string = input_string;
if (string.isEmpty()) {
string.decref();
return RocStr.empty();
}
const bytes_ptr = string.asU8ptrMut();
const leading_bytes = countLeadingWhitespaceBytes(string);
const original_len = string.len();
if (original_len == leading_bytes) {
string.decref();
return RocStr.empty();
}
const trailing_bytes = countTrailingWhitespaceBytes(string);
const new_len = original_len - leading_bytes - trailing_bytes;
if (string.isSmallStr()) {
// Just create another small string of the correct bytes.
// No need to decref because it is a small string.
return RocStr.init(string.asU8ptr() + leading_bytes, new_len);
} else if (leading_bytes == 0 and string.isUnique()) {
// Big and unique with no leading bytes to remove.
// Just take ownership and shrink the length.
var new_string = string;
new_string.length = new_len;
return new_string;
} else if (string.isSeamlessSlice()) {
// Already a seamless slice, just update the range.
return RocStr{
.bytes = bytes_ptr + leading_bytes,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = string.capacity_or_alloc_ptr,
};
} else {
// Not unique or removing leading bytes, just make a slice.
return RocStr{
.bytes = bytes_ptr + leading_bytes,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = @intFromPtr(bytes_ptr) >> 1,
};
}
}
pub fn strTrimStart(input_string: RocStr) callconv(.C) RocStr {
var string = input_string;
if (string.isEmpty()) {
string.decref();
return RocStr.empty();
}
const bytes_ptr = string.asU8ptrMut();
const leading_bytes = countLeadingWhitespaceBytes(string);
const original_len = string.len();
if (original_len == leading_bytes) {
string.decref();
return RocStr.empty();
}
const new_len = original_len - leading_bytes;
if (string.isSmallStr()) {
// Just create another small string of the correct bytes.
// No need to decref because it is a small string.
return RocStr.init(string.asU8ptr() + leading_bytes, new_len);
} else if (leading_bytes == 0 and string.isUnique()) {
// Big and unique with no leading bytes to remove.
// Just take ownership and shrink the length.
var new_string = string;
new_string.length = new_len;
return new_string;
} else if (string.isSeamlessSlice()) {
// Already a seamless slice, just update the range.
return RocStr{
.bytes = bytes_ptr + leading_bytes,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = string.capacity_or_alloc_ptr,
};
} else {
// Not unique or removing leading bytes, just make a slice.
return RocStr{
.bytes = bytes_ptr + leading_bytes,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = @intFromPtr(bytes_ptr) >> 1,
};
}
}
pub fn strTrimEnd(input_string: RocStr) callconv(.C) RocStr {
var string = input_string;
if (string.isEmpty()) {
string.decref();
return RocStr.empty();
}
const bytes_ptr = string.asU8ptrMut();
const trailing_bytes = countTrailingWhitespaceBytes(string);
const original_len = string.len();
if (original_len == trailing_bytes) {
string.decref();
return RocStr.empty();
}
const new_len = original_len - trailing_bytes;
if (string.isSmallStr()) {
// Just create another small string of the correct bytes.
// No need to decref because it is a small string.
return RocStr.init(string.asU8ptr(), new_len);
} else if (string.isUnique()) {
// Big and unique with no leading bytes to remove.
// Just take ownership and shrink the length.
var new_string = string;
new_string.length = new_len;
return new_string;
} else if (string.isSeamlessSlice()) {
// Already a seamless slice, just update the range.
return RocStr{
.bytes = bytes_ptr,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = string.capacity_or_alloc_ptr,
};
} else {
// Not unique, just make a slice.
return RocStr{
.bytes = bytes_ptr,
.length = new_len | SEAMLESS_SLICE_BIT,
.capacity_or_alloc_ptr = @intFromPtr(bytes_ptr) >> 1,
};
}
}
fn countLeadingWhitespaceBytes(string: RocStr) usize {
var byte_count: usize = 0;
var bytes = string.asU8ptr()[0..string.len()];
var iter = unicode.Utf8View.initUnchecked(bytes).iterator();
while (iter.nextCodepoint()) |codepoint| {
if (isWhitespace(codepoint)) {
byte_count += unicode.utf8CodepointSequenceLength(codepoint) catch break;
} else {
break;
}
}
return byte_count;
}
fn countTrailingWhitespaceBytes(string: RocStr) usize {
var byte_count: usize = 0;
var bytes = string.asU8ptr()[0..string.len()];
var iter = ReverseUtf8View.initUnchecked(bytes).iterator();
while (iter.nextCodepoint()) |codepoint| {
if (isWhitespace(codepoint)) {
byte_count += unicode.utf8CodepointSequenceLength(codepoint) catch break;
} else {
break;
}
}
return byte_count;
}
/// A backwards version of Utf8View from std.unicode
const ReverseUtf8View = struct {
bytes: []const u8,
pub fn initUnchecked(s: []const u8) ReverseUtf8View {
return ReverseUtf8View{ .bytes = s };
}
pub fn iterator(s: ReverseUtf8View) ReverseUtf8Iterator {
return ReverseUtf8Iterator{
.bytes = s.bytes,
.i = if (s.bytes.len > 0) s.bytes.len - 1 else null,
};
}
};
/// A backwards version of Utf8Iterator from std.unicode
const ReverseUtf8Iterator = struct {
bytes: []const u8,
// NOTE null signifies complete/empty
i: ?usize,
pub fn nextCodepointSlice(it: *ReverseUtf8Iterator) ?[]const u8 {
if (it.i) |index| {
var i = index;
// NOTE this relies on the string being valid utf8 to not run off the end
while (!utf8BeginByte(it.bytes[i])) {
i -= 1;
}
const cp_len = unicode.utf8ByteSequenceLength(it.bytes[i]) catch unreachable;
const slice = it.bytes[i .. i + cp_len];
it.i = if (i == 0) null else i - 1;
return slice;
} else {
return null;
}
}
pub fn nextCodepoint(it: *ReverseUtf8Iterator) ?u21 {
const slice = it.nextCodepointSlice() orelse return null;
return switch (slice.len) {
1 => @as(u21, slice[0]),
2 => unicode.utf8Decode2(slice) catch unreachable,
3 => unicode.utf8Decode3(slice) catch unreachable,
4 => unicode.utf8Decode4(slice) catch unreachable,
else => unreachable,
};
}
};
fn utf8BeginByte(byte: u8) bool {
return switch (byte) {
0b1000_0000...0b1011_1111 => false,
else => true,
};
}
test "strTrim: empty" {
const trimmedEmpty = strTrim(RocStr.empty());
try expect(trimmedEmpty.eq(RocStr.empty()));
}
test "strTrim: null byte" {
const bytes = [_]u8{0};
const original = RocStr.init(&bytes, 1);
try expectEqual(@as(usize, 1), original.len());
try expectEqual(@as(usize, SMALL_STR_MAX_LENGTH), original.getCapacity());
const original_with_capacity = reserve(original, 40);
defer original_with_capacity.decref();
try expectEqual(@as(usize, 1), original_with_capacity.len());
try expectEqual(@as(usize, 64), original_with_capacity.getCapacity());
const trimmed = strTrim(original.clone());
defer trimmed.decref();
try expect(original.eq(trimmed));
}
test "strTrim: blank" {
const original_bytes = " ";
const original = RocStr.init(original_bytes, original_bytes.len);
const trimmed = strTrim(original);
defer trimmed.decref();
try expect(trimmed.eq(RocStr.empty()));
}
test "strTrim: large to large" {
const original_bytes = " hello even more giant world ";
const original = RocStr.init(original_bytes, original_bytes.len);
try expect(!original.isSmallStr());
const expected_bytes = "hello even more giant world";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(!expected.isSmallStr());
const trimmed = strTrim(original);
defer trimmed.decref();
try expect(trimmed.eq(expected));
}
test "strTrim: large to small sized slice" {
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
try expect(!original.isSmallStr());
const expected_bytes = "hello";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
try expect(original.isUnique());
const trimmed = strTrim(original);
defer trimmed.decref();
try expect(trimmed.eq(expected));
try expect(!trimmed.isSmallStr());
}
test "strTrim: small to small" {
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
try expect(original.isSmallStr());
const expected_bytes = "hello";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
const trimmed = strTrim(original);
try expect(trimmed.eq(expected));
try expect(trimmed.isSmallStr());
}
test "strTrimStart: empty" {
const trimmedEmpty = strTrimStart(RocStr.empty());
try expect(trimmedEmpty.eq(RocStr.empty()));
}
test "strTrimStart: blank" {
const original_bytes = " ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
const trimmed = strTrimStart(original);
try expect(trimmed.eq(RocStr.empty()));
}
test "strTrimStart: large to large" {
const original_bytes = " hello even more giant world ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
try expect(!original.isSmallStr());
const expected_bytes = "hello even more giant world ";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(!expected.isSmallStr());
const trimmed = strTrimStart(original);
try expect(trimmed.eq(expected));
}
test "strTrimStart: large to small" {
// `original` will be consumed by the concat; do not free explicitly
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
try expect(!original.isSmallStr());
const expected_bytes = "hello ";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
const trimmed = strTrimStart(original);
defer trimmed.decref();
try expect(trimmed.eq(expected));
try expect(!trimmed.isSmallStr());
}
test "strTrimStart: small to small" {
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
try expect(original.isSmallStr());
const expected_bytes = "hello ";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
const trimmed = strTrimStart(original);
try expect(trimmed.eq(expected));
try expect(trimmed.isSmallStr());
}
test "strTrimEnd: empty" {
const trimmedEmpty = strTrimEnd(RocStr.empty());
try expect(trimmedEmpty.eq(RocStr.empty()));
}
test "strTrimEnd: blank" {
const original_bytes = " ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
const trimmed = strTrimEnd(original);
try expect(trimmed.eq(RocStr.empty()));
}
test "strTrimEnd: large to large" {
const original_bytes = " hello even more giant world ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
try expect(!original.isSmallStr());
const expected_bytes = " hello even more giant world";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(!expected.isSmallStr());
const trimmed = strTrimEnd(original);
try expect(trimmed.eq(expected));
}
test "strTrimEnd: large to small" {
// `original` will be consumed by the concat; do not free explicitly
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
try expect(!original.isSmallStr());
const expected_bytes = " hello";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
const trimmed = strTrimEnd(original);
defer trimmed.decref();
try expect(trimmed.eq(expected));
try expect(!trimmed.isSmallStr());
}
test "strTrimEnd: small to small" {
const original_bytes = " hello ";
const original = RocStr.init(original_bytes, original_bytes.len);
defer original.decref();
try expect(original.isSmallStr());
const expected_bytes = " hello";
const expected = RocStr.init(expected_bytes, expected_bytes.len);
defer expected.decref();
try expect(expected.isSmallStr());
const trimmed = strTrimEnd(original);
try expect(trimmed.eq(expected));
try expect(trimmed.isSmallStr());
}
test "ReverseUtf8View: hello world" {
const original_bytes = "hello world";
const expected_bytes = "dlrow olleh";
var i: usize = 0;
var iter = ReverseUtf8View.initUnchecked(original_bytes).iterator();
while (iter.nextCodepoint()) |codepoint| {
try expect(expected_bytes[i] == codepoint);
i += 1;
}
}
test "ReverseUtf8View: empty" {
const original_bytes = "";
var iter = ReverseUtf8View.initUnchecked(original_bytes).iterator();
while (iter.nextCodepoint()) |_| {
try expect(false);
}
}
test "capacity: small string" {
const data_bytes = "foobar";
var data = RocStr.init(data_bytes, data_bytes.len);
defer data.decref();
try expectEqual(data.getCapacity(), SMALL_STR_MAX_LENGTH);
}
test "capacity: big string" {
const data_bytes = "a string so large that it must be heap-allocated";
var data = RocStr.init(data_bytes, data_bytes.len);
defer data.decref();
try expect(data.getCapacity() >= data_bytes.len);
}
pub fn reserveC(string: RocStr, spare_u64: u64) callconv(.C) RocStr {
return reserve(string, @intCast(spare_u64));
}
fn reserve(string: RocStr, spare: usize) RocStr {
const old_length = string.len();
if (string.getCapacity() >= old_length + spare) {
return string;
} else {
var output = string.reallocate(old_length + spare);
output.setLen(old_length);
return output;
}
}
pub fn withCapacityC(capacity: u64) callconv(.C) RocStr {
var str = RocStr.allocate(@intCast(capacity));
str.setLen(0);
return str;
}
pub fn strCloneTo(
string: RocStr,
ptr: [*]u8,
offset: usize,
extra_offset: usize,
) callconv(.C) usize {
const WIDTH: usize = @sizeOf(RocStr);
if (string.isSmallStr()) {
const array: [@sizeOf(RocStr)]u8 = @as([@sizeOf(RocStr)]u8, @bitCast(string));
var i: usize = 0;
while (i < WIDTH) : (i += 1) {
ptr[offset + i] = array[i];
}
return extra_offset;
} else {
const slice = string.asSlice();
var relative = string;
relative.bytes = @as(?[*]u8, @ptrFromInt(extra_offset)); // i.e. just after the string struct
// write the string struct
const array = relative.asArray();
@memcpy(ptr[offset..(offset + WIDTH)], array[0..WIDTH]);
// write the string bytes just after the struct
@memcpy(ptr[extra_offset..(extra_offset + slice.len)], slice);
return extra_offset + slice.len;
}
}
pub fn strAllocationPtr(
string: RocStr,
) callconv(.C) ?[*]u8 {
return string.getAllocationPtr();
}
pub fn strReleaseExcessCapacity(
string: RocStr,
) callconv(.C) RocStr {
const old_length = string.len();
// We use the direct list.capacity_or_alloc_ptr to make sure both that there is no extra capacity and that it isn't a seamless slice.
if (string.isSmallStr()) {
// SmallStr has no excess capacity.
return string;
} else if (string.isUnique() and !string.isSeamlessSlice() and string.getCapacity() == old_length) {
return string;
} else if (old_length == 0) {
string.decref();
return RocStr.empty();
} else {
var output = RocStr.allocateExact(old_length);
const source_ptr = string.asU8ptr();
const dest_ptr = output.asU8ptrMut();
@memcpy(dest_ptr[0..old_length], source_ptr[0..old_length]);
string.decref();
return output;
}
}