Refactoring Node

crates/compiler/fmt/src/node.rs

@@ -0,0 +1,90 @@
+use bumpalo::Bump;
+use roc_parse::ast::{CommentOrNewline, Spaces, TypeAnnotation};
+
+use crate::{
+    annotation::{Formattable, Newlines, Parens},
+    collection::Braces,
+    spaces::fmt_spaces,
+    Buf,
+};
+
+pub type Sp<'a> = &'a [CommentOrNewline<'a>];
+
+#[derive(Copy, Clone, Debug)]
+pub enum Node<'a> {
+    Literal(&'a str),
+    Sequence(&'a Node<'a>, &'a [(Sp<'a>, Node<'a>)]),
+    DelimitedSequence(Braces, &'a [(Sp<'a>, Node<'a>)], Sp<'a>),
+    TypeAnnotation(TypeAnnotation<'a>),
+}
+
+pub trait Nodify<'a> {
+    fn to_node<'b>(&'a self, arena: &'b Bump, parens: Parens) -> Spaces<'b, Node<'b>>
+    where
+        'a: 'b;
+}
+
+impl<'a> Formattable for Node<'a> {
+    fn is_multiline(&self) -> bool {
+        match self {
+            Node::DelimitedSequence(_braces, lefts, right) => {
+                right.is_empty()
+                    && lefts
+                        .iter()
+                        .any(|(sp, l)| l.is_multiline() || !sp.is_empty())
+            }
+            Node::Sequence(first, rest) => {
+                first.is_multiline()
+                    || rest
+                        .iter()
+                        .any(|(sp, l)| l.is_multiline() || !sp.is_empty())
+            }
+            Node::TypeAnnotation(type_annotation) => type_annotation.is_multiline(),
+            Node::Literal(_) => false,
+        }
+    }
+
+    fn format_with_options(&self, buf: &mut Buf, parens: Parens, newlines: Newlines, indent: u16) {
+        match self {
+            Node::DelimitedSequence(braces, lefts, right) => {
+                buf.indent(indent);
+                buf.push(braces.start());
+
+                for (sp, l) in *lefts {
+                    if !sp.is_empty() {
+                        fmt_spaces(buf, sp.iter(), indent);
+                    }
+
+                    l.format_with_options(buf, parens, newlines, indent);
+                }
+
+                if !right.is_empty() {
+                    fmt_spaces(buf, right.iter(), indent);
+                }
+
+                buf.indent(indent);
+                buf.push(braces.end());
+            }
+            Node::Sequence(first, rest) => {
+                first.format_with_options(buf, parens, newlines, indent);
+
+                for (sp, l) in *rest {
+                    if !sp.is_empty() {
+                        fmt_spaces(buf, sp.iter(), indent);
+                    } else {
+                        buf.spaces(1);
+                    }
+
+                    l.format_with_options(buf, parens, newlines, indent);
+                }
+            }
+            Node::TypeAnnotation(type_annotation) => {
+                type_annotation.format_with_options(buf, parens, newlines, indent);
+            }
+            Node::Literal(text) => {
+                buf.indent(indent);
+                buf.push_str(text);
+            }
+        }
+    }
+}