Merge pull request #1759 from rtfeldman/docs_markup

re-use editor markup for docs

Cargo.lock

@@ -3228,8 +3228,10 @@ dependencies = [
  "libc",
  "page_size",
  "pretty_assertions 0.6.1",
+ "roc_builtins",
  "roc_can",
  "roc_collections",
+ "roc_load",
  "roc_module",
  "roc_parse",
  "roc_problem",
@@ -3414,14 +3416,19 @@ dependencies = [
  "maplit",
  "pretty_assertions 0.5.1",
  "pulldown-cmark",
+ "roc_ast",
  "roc_builtins",
  "roc_can",
+ "roc_code_markup",
  "roc_collections",
+ "roc_fmt",
  "roc_load",
  "roc_module",
  "roc_parse",
  "roc_region",
  "roc_types",
+ "tempfile",
+ "uuid",
 ]
 
 [[package]]

ast/Cargo.toml

@@ -7,6 +7,7 @@ edition = "2018"
 description = "AST as used by the editor and (soon) docs. In contrast to the compiler, these types do not keep track of a location in a file."
 
 [dependencies]
+roc_builtins = { path = "../compiler/builtins"}
 roc_can = { path = "../compiler/can" }
 roc_collections = { path = "../compiler/collections" }
 roc_region = { path = "../compiler/region" }
@@ -15,6 +16,7 @@ roc_parse = { path = "../compiler/parse" }
 roc_problem = { path = "../compiler/problem" }
 roc_types = { path = "../compiler/types" }
 roc_unify = { path = "../compiler/unify"}
+roc_load = { path = "../compiler/load" }
 arraystring = "0.3.0"
 bumpalo = { version = "3.6.1", features = ["collections"] }
 libc = "0.2"

ast/src/canonicalization/canonicalize.rs

@@ -9,7 +9,7 @@ use crate::{
             def::def::References,
             expr::{
                 expr2::{Expr2, ExprId, WhenBranch},
-                expr_to_expr2::to_expr2,
+                expr_to_expr2::expr_to_expr2,
                 output::Output,
                 record_field::RecordField,
             },
@@ -147,7 +147,8 @@ fn canonicalize_field<'a>(
         // Both a label and a value, e.g. `{ name: "blah" }`
         RequiredValue(label, _, loc_expr) => {
             let field_var = env.var_store.fresh();
-            let (loc_can_expr, output) = to_expr2(env, scope, &loc_expr.value, loc_expr.region);
+            let (loc_can_expr, output) =
+                expr_to_expr2(env, scope, &loc_expr.value, loc_expr.region);
 
             Ok(CanonicalField::LabelAndValue {
                 label: label.value,
@@ -211,7 +212,7 @@ pub(crate) fn canonicalize_when_branch<'a>(
     }
 
     let (value, mut branch_output) =
-        to_expr2(env, &mut scope, &branch.value.value, branch.value.region);
+        expr_to_expr2(env, &mut scope, &branch.value.value, branch.value.region);
     let value_id = env.pool.add(value);
     env.set_region(value_id, branch.value.region);
 
@@ -219,7 +220,7 @@ pub(crate) fn canonicalize_when_branch<'a>(
         None => None,
         Some(loc_expr) => {
             let (can_guard, guard_branch_output) =
-                to_expr2(env, &mut scope, &loc_expr.value, loc_expr.region);
+                expr_to_expr2(env, &mut scope, &loc_expr.value, loc_expr.region);
 
             let expr_id = env.pool.add(can_guard);
             env.set_region(expr_id, loc_expr.region);

ast/src/lang/core/def/def.rs

@@ -27,7 +27,7 @@ use ven_graph::{strongly_connected_components, topological_sort_into_groups};
 use crate::{
     lang::{
         core::{
-            expr::{expr2::Expr2, expr_to_expr2::to_expr2, output::Output},
+            expr::{expr2::Expr2, expr_to_expr2::expr_to_expr2, output::Output},
             fun_def::FunctionDef,
             pattern::{self, symbols_from_pattern, to_pattern_id, Pattern2, PatternId},
             types::{to_annotation2, Alias, Annotation2, Signature, Type2, TypeId},
@@ -472,7 +472,7 @@ fn canonicalize_pending_def<'a>(
                     };
 
                     let (loc_can_expr, can_output) =
-                        to_expr2(env, scope, &loc_expr.value, loc_expr.region);
+                        expr_to_expr2(env, scope, &loc_expr.value, loc_expr.region);
 
                     output.references.union_mut(can_output.references.clone());
 
@@ -639,7 +639,8 @@ fn canonicalize_pending_def<'a>(
                 env.closure_name_symbol = Some(*defined_symbol);
             };
 
-            let (loc_can_expr, can_output) = to_expr2(env, scope, &loc_expr.value, loc_expr.region);
+            let (loc_can_expr, can_output) =
+                expr_to_expr2(env, scope, &loc_expr.value, loc_expr.region);
 
             output.references.union_mut(can_output.references.clone());
 

ast/src/lang/core/def/def_to_def2.rs

@@ -20,11 +20,11 @@ pub fn defs_to_defs2<'a>(
 ) -> Vec<Def2> {
     parsed_defs
         .iter()
-        .map(|loc| to_def2_from_def(arena, env, scope, &loc.value, region))
+        .map(|loc| def_to_def2(arena, env, scope, &loc.value, region))
         .collect()
 }
 
-pub fn to_def2_from_def<'a>(
+pub fn def_to_def2<'a>(
     arena: &'a Bump,
     env: &mut Env<'a>,
     scope: &mut Scope,
@@ -34,8 +34,8 @@ pub fn to_def2_from_def<'a>(
     use roc_parse::ast::Def::*;
 
     match parsed_def {
-        SpaceBefore(inner_def, _) => to_def2_from_def(arena, env, scope, inner_def, region),
+        SpaceBefore(inner_def, _) => def_to_def2(arena, env, scope, inner_def, region),
-        SpaceAfter(inner_def, _) => to_def2_from_def(arena, env, scope, inner_def, region),
+        SpaceAfter(inner_def, _) => def_to_def2(arena, env, scope, inner_def, region),
         Body(&loc_pattern, &loc_expr) => {
             // TODO loc_pattern use identifier
             let expr2 = loc_expr_to_expr2(arena, loc_expr, env, scope, region).0;

ast/src/lang/core/expr/expr_to_expr2.rs

@@ -36,12 +36,12 @@ pub fn loc_expr_to_expr2<'a>(
 ) -> (Expr2, Output) {
     let desugared_loc_expr = desugar_expr(arena, arena.alloc(loc_expr));
 
-    to_expr2(env, scope, arena.alloc(desugared_loc_expr.value), region)
+    expr_to_expr2(env, scope, arena.alloc(desugared_loc_expr.value), region)
 }
 
 const ZERO: Region = Region::zero();
 
-pub fn to_expr2<'a>(
+pub fn expr_to_expr2<'a>(
     env: &mut Env<'a>,
     scope: &mut Scope,
     parse_expr: &'a roc_parse::ast::Expr<'a>,
@@ -139,7 +139,7 @@ pub fn to_expr2<'a>(
             let elems: PoolVec<ExprId> = PoolVec::with_capacity(items.len() as u32, env.pool);
 
             for (node_id, item) in elems.iter_node_ids().zip(items.iter()) {
-                let (expr, sub_output) = to_expr2(env, scope, &item.value, item.region);
+                let (expr, sub_output) = expr_to_expr2(env, scope, &item.value, item.region);
 
                 output_ref.union(sub_output);
 
@@ -188,7 +188,7 @@ pub fn to_expr2<'a>(
             final_comments: _,
         } => {
             let (can_update, update_out) =
-                to_expr2(env, scope, &loc_update.value, loc_update.region);
+                expr_to_expr2(env, scope, &loc_update.value, loc_update.region);
 
             if let Expr2::Var(symbol) = &can_update {
                 match canonicalize_fields(env, scope, fields) {
@@ -309,10 +309,11 @@ pub fn to_expr2<'a>(
             let mut output = Output::default();
 
             for (condition, then_branch) in branches.iter() {
-                let (cond, cond_output) = to_expr2(env, scope, &condition.value, condition.region);
+                let (cond, cond_output) =
+                    expr_to_expr2(env, scope, &condition.value, condition.region);
 
                 let (then_expr, then_output) =
-                    to_expr2(env, scope, &then_branch.value, then_branch.region);
+                    expr_to_expr2(env, scope, &then_branch.value, then_branch.region);
 
                 output.references.union_mut(cond_output.references);
                 output.references.union_mut(then_output.references);
@@ -321,7 +322,7 @@ pub fn to_expr2<'a>(
             }
 
             let (else_expr, else_output) =
-                to_expr2(env, scope, &final_else.value, final_else.region);
+                expr_to_expr2(env, scope, &final_else.value, final_else.region);
 
             output.references.union_mut(else_output.references);
 
@@ -338,7 +339,8 @@ pub fn to_expr2<'a>(
         When(loc_cond, branches) => {
             // Infer the condition expression's type.
             let cond_var = env.var_store.fresh();
-            let (can_cond, mut output) = to_expr2(env, scope, &loc_cond.value, loc_cond.region);
+            let (can_cond, mut output) =
+                expr_to_expr2(env, scope, &loc_cond.value, loc_cond.region);
 
             // the condition can never be a tail-call
             output.tail_call = None;
@@ -411,7 +413,7 @@ pub fn to_expr2<'a>(
             }
 
             let (body_expr, new_output) =
-                to_expr2(env, &mut scope, &loc_body_expr.value, loc_body_expr.region);
+                expr_to_expr2(env, &mut scope, &loc_body_expr.value, loc_body_expr.region);
 
             let mut captured_symbols: MutSet<Symbol> =
                 new_output.references.lookups.iter().copied().collect();
@@ -501,7 +503,7 @@ pub fn to_expr2<'a>(
             let fn_region = loc_fn.region;
 
             // Canonicalize the function expression and its arguments
-            let (fn_expr, mut output) = to_expr2(env, scope, &loc_fn.value, fn_region);
+            let (fn_expr, mut output) = expr_to_expr2(env, scope, &loc_fn.value, fn_region);
 
             // The function's return type
             let args = PoolVec::with_capacity(loc_args.len() as u32, env.pool);
@@ -592,7 +594,8 @@ pub fn to_expr2<'a>(
 
             // The def as a whole is a tail call iff its return expression is a tail call.
             // Use its output as a starting point because its tail_call already has the right answer!
-            let (ret_expr, mut output) = to_expr2(env, &mut scope, &loc_ret.value, loc_ret.region);
+            let (ret_expr, mut output) =
+                expr_to_expr2(env, &mut scope, &loc_ret.value, loc_ret.region);
 
             output
                 .introduced_variables
@@ -704,7 +707,7 @@ pub fn to_expr_id<'a>(
     parse_expr: &'a roc_parse::ast::Expr<'a>,
     region: Region,
 ) -> (ExprId, Output) {
-    let (expr, output) = to_expr2(env, scope, parse_expr, region);
+    let (expr, output) = expr_to_expr2(env, scope, parse_expr, region);
 
     (env.add(expr, region), output)
 }

ast/src/lang/core/expr/mod.rs

@@ -1,6 +1,6 @@
 pub mod expr2;
 pub mod expr2_to_string;
-pub(crate) mod expr_to_expr2;
+pub mod expr_to_expr2;
 mod introduced_vars;
 pub(crate) mod output;
 pub mod record_field;

ast/src/lang/core/str.rs

@@ -3,7 +3,7 @@ use roc_parse::ast::StrLiteral;
 
 use crate::{
     ast_error::{ASTResult, UnexpectedASTNode},
-    lang::{core::expr::expr_to_expr2::to_expr2, env::Env, scope::Scope},
+    lang::{core::expr::expr_to_expr2::expr_to_expr2, env::Env, scope::Scope},
     mem_pool::{pool::Pool, pool_str::PoolStr, pool_vec::PoolVec},
 };
 
@@ -94,7 +94,7 @@ fn flatten_str_lines<'a>(
                         }
 
                         let (loc_expr, new_output) =
-                            to_expr2(env, scope, loc_expr.value, loc_expr.region);
+                            expr_to_expr2(env, scope, loc_expr.value, loc_expr.region);
 
                         output.union(new_output);
 

ast/src/lib.rs

@@ -3,5 +3,6 @@ mod canonicalization;
 pub mod constrain;
 pub mod lang;
 pub mod mem_pool;
+pub mod module;
 pub mod parse;
 pub mod solve_type;

ast/src/module.rs

@@ -0,0 +1,39 @@
+use std::path::Path;
+
+use bumpalo::Bump;
+use roc_collections::all::MutMap;
+use roc_load::file::LoadedModule;
+
+pub fn load_module(src_file: &Path) -> LoadedModule {
+    let subs_by_module = MutMap::default();
+
+    let arena = Bump::new();
+    let loaded = roc_load::file::load_and_typecheck(
+        &arena,
+        src_file.to_path_buf(),
+        arena.alloc(roc_builtins::std::standard_stdlib()),
+        src_file.parent().unwrap_or_else(|| {
+            panic!(
+                "src_file {:?} did not have a parent directory but I need to have one.",
+                src_file
+            )
+        }),
+        subs_by_module,
+        8,
+        roc_can::builtins::builtin_defs_map,
+    );
+
+    match loaded {
+        Ok(x) => x,
+        Err(roc_load::file::LoadingProblem::FormattedReport(report)) => {
+            panic!(
+                "Failed to load module from src_file {:?}. Report: {:?}",
+                src_file, report
+            );
+        }
+        Err(e) => panic!(
+            "Failed to load module from src_file {:?}: {:?}",
+            src_file, e
+        ),
+    }
+}

cli/src/lib.rs

@@ -240,7 +240,7 @@ pub fn build_app<'a>() -> App<'a> {
 }
 
 pub fn docs(files: Vec<PathBuf>) {
-    roc_docs::generate(
+    roc_docs::generate_docs_html(
         files,
         roc_builtins::std::standard_stdlib(),
         Path::new("./generated-docs"),

code_markup/src/markup/common_nodes.rs

@@ -19,7 +19,7 @@ pub fn new_comma_mn(expr_id: ExprId, parent_id_opt: Option<MarkNodeId>) -> Marku
     MarkupNode::Text {
         content: nodes::COMMA.to_owned(),
         ast_node_id: ASTNodeId::AExprId(expr_id),
-        syn_high_style: HighlightStyle::Blank,
+        syn_high_style: HighlightStyle::Comma,
         attributes: Attributes::default(),
         parent_id_opt,
         newlines_at_end: 0,

code_markup/src/markup/nodes.rs

@@ -13,7 +13,6 @@ use super::{
 };
 
 use crate::markup_error::{ExpectedTextNode, NestedNodeMissingChild, NestedNodeRequired};
-use bumpalo::Bump;
 use roc_ast::{
     ast_error::ASTResult,
     lang::{
@@ -305,9 +304,8 @@ fn new_markup_node(
     mark_node_pool.add(node)
 }
 
-pub fn def2_to_markup<'a, 'b>(
+pub fn def2_to_markup<'a>(
-    arena: &'a Bump,
+    env: &mut Env<'a>,
-    env: &mut Env<'b>,
     def2: &Def2,
     def2_node_id: DefId,
     mark_node_pool: &mut SlowPool,
@@ -321,7 +319,6 @@ pub fn def2_to_markup<'a, 'b>(
             expr_id,
         } => {
             let expr_mn_id = expr2_to_markup(
-                arena,
                 env,
                 env.pool.get(*expr_id),
                 *expr_id,
@@ -347,9 +344,8 @@ pub fn def2_to_markup<'a, 'b>(
 }
 
 // make Markup Nodes: generate String representation, assign Highlighting Style
-pub fn expr2_to_markup<'a, 'b>(
+pub fn expr2_to_markup<'a>(
-    arena: &'a Bump,
+    env: &mut Env<'a>,
-    env: &mut Env<'b>,
     expr2: &Expr2,
     expr2_node_id: ExprId,
     mark_node_pool: &mut SlowPool,
@@ -380,7 +376,7 @@ pub fn expr2_to_markup<'a, 'b>(
         ),
         Expr2::Call { expr: expr_id, .. } => {
             let expr = env.pool.get(*expr_id);
-            expr2_to_markup(arena, env, expr, *expr_id, mark_node_pool, interns)?
+            expr2_to_markup(env, expr, *expr_id, mark_node_pool, interns)?
         }
         Expr2::Var(symbol) => {
             //TODO make bump_format with arena
@@ -398,7 +394,6 @@ pub fn expr2_to_markup<'a, 'b>(
                 let sub_expr2 = env.pool.get(*node_id);
 
                 children_ids.push(expr2_to_markup(
-                    arena,
                     env,
                     sub_expr2,
                     *node_id,
@@ -460,7 +455,6 @@ pub fn expr2_to_markup<'a, 'b>(
 
                         let sub_expr2 = env.pool.get(*sub_expr2_node_id);
                         children_ids.push(expr2_to_markup(
-                            arena,
                             env,
                             sub_expr2,
                             *sub_expr2_node_id,
@@ -520,7 +514,6 @@ pub fn expr2_to_markup<'a, 'b>(
                     expr_var: _,
                 } => {
                     let body_mn_id = expr2_to_markup(
-                        arena,
                         env,
                         env.pool.get(*expr_id),
                         *expr_id,
@@ -797,9 +790,8 @@ fn add_header_mn_list(
         .collect()
 }
 
-pub fn ast_to_mark_nodes<'a, 'b>(
+pub fn ast_to_mark_nodes<'a>(
-    arena: &'a Bump,
+    env: &mut Env<'a>,
-    env: &mut Env<'b>,
     ast: &AST,
     mark_node_pool: &mut SlowPool,
     interns: &Interns,
@@ -809,11 +801,11 @@ pub fn ast_to_mark_nodes<'a, 'b>(
     for &def_id in ast.def_ids.iter() {
         let def2 = env.pool.get(def_id);
 
-        let expr2_markup_id = def2_to_markup(arena, env, def2, def_id, mark_node_pool, interns)?;
+        let def2_markup_id = def2_to_markup(env, def2, def_id, mark_node_pool, interns)?;
 
-        set_parent_for_all(expr2_markup_id, mark_node_pool);
+        set_parent_for_all(def2_markup_id, mark_node_pool);
 
-        all_mark_node_ids.push(expr2_markup_id);
+        all_mark_node_ids.push(def2_markup_id);
     }
 
     Ok(all_mark_node_ids)

code_markup/src/syntax_highlight.rs

@@ -6,6 +6,7 @@ use crate::colors::{self, from_hsb, RgbaTup};
 #[derive(Hash, Eq, PartialEq, Copy, Clone, Debug, Deserialize, Serialize)]
 pub enum HighlightStyle {
     Operator, // =+-<>...
+    Comma,
     String,
     FunctionName,
     Type,
@@ -25,6 +26,7 @@ pub fn default_highlight_map() -> HashMap<HighlightStyle, RgbaTup> {
     let mut highlight_map = HashMap::new();
     [
         (Operator, colors::WHITE),
+        (Comma, from_hsb(258, 50, 90)),
         (String, from_hsb(346, 65, 97)),
         (FunctionName, colors::WHITE),
         (Type, colors::WHITE),

compiler/can/src/scope.rs

@@ -83,7 +83,7 @@ impl Scope {
         self.idents.len()
     }
 
-    pub fn lookup(&mut self, ident: &Ident, region: Region) -> Result<Symbol, RuntimeError> {
+    pub fn lookup(&self, ident: &Ident, region: Region) -> Result<Symbol, RuntimeError> {
         match self.idents.get(ident) {
             Some((symbol, _)) => Ok(*symbol),
             None => Err(RuntimeError::LookupNotInScope(

docs/Cargo.toml

@@ -9,9 +9,12 @@ edition = "2018"
 
 [dependencies]
 pulldown-cmark = { version = "0.8", default-features = false }
+roc_ast = { path = "../ast" }
 roc_load = { path = "../compiler/load" }
 roc_builtins = { path = "../compiler/builtins" }
 roc_can = { path = "../compiler/can" }
+roc_code_markup = { path = "../code_markup"}
+roc_fmt = { path = "../compiler/fmt" }
 roc_module = { path = "../compiler/module" }
 roc_region = { path = "../compiler/region" }
 roc_types = { path = "../compiler/types" }
@@ -22,3 +25,5 @@ bumpalo = { version = "3.2", features = ["collections"] }
 [dev-dependencies]
 pretty_assertions = "0.5.1"
 maplit = "1.0.1"
+tempfile = "3.2.0"
+uuid = { version = "0.8", features = ["v4"] }

docs/src/def.rs

@@ -0,0 +1,79 @@
+use bumpalo::{collections::String as BumpString, Bump};
+use roc_ast::{
+    ast_error::ASTResult,
+    lang::{self, core::def::def_to_def2::def_to_def2},
+    mem_pool::pool::Pool,
+};
+use roc_code_markup::{markup::nodes::def2_to_markup, slow_pool::SlowPool};
+use roc_module::symbol::{IdentIds, Interns, ModuleId, ModuleIds};
+use roc_region::all::Region;
+use roc_types::subs::VarStore;
+
+use crate::html::mark_node_to_html;
+
+// html is written to buf
+pub fn defs_to_html<'a>(
+    buf: &mut BumpString<'a>,
+    defs: Vec<roc_parse::ast::Def<'a>>,
+    env_module_id: ModuleId,
+    env_module_ids: &'a ModuleIds,
+    interns: &Interns,
+) {
+    let mut env_pool = Pool::with_capacity(1024);
+    let env_arena = Bump::new();
+
+    let mut var_store = VarStore::default();
+    let dep_idents = IdentIds::exposed_builtins(8);
+    let exposed_ident_ids = IdentIds::default();
+
+    let def_arena = Bump::new();
+
+    let mut env = lang::env::Env::new(
+        env_module_id,
+        &env_arena,
+        &mut env_pool,
+        &mut var_store,
+        dep_idents,
+        env_module_ids,
+        exposed_ident_ids,
+    );
+
+    let mut scope = lang::scope::Scope::new(env.home, env.pool, env.var_store);
+    let region = Region::new(0, 0, 0, 0);
+
+    for def in defs.iter() {
+        // TODO remove unwrap
+        write_def_to_bump_str_html(&def_arena, &mut env, &mut scope, region, def, interns, buf)
+            .unwrap();
+    }
+}
+
+fn write_def_to_bump_str_html<'a, 'b>(
+    arena: &'a Bump,
+    env: &mut lang::env::Env<'a>,
+    scope: &mut lang::scope::Scope,
+    region: Region,
+    def: &'a roc_parse::ast::Def<'a>,
+    interns: &Interns,
+    buf: &mut BumpString<'b>,
+) -> ASTResult<()> {
+    let def2 = def_to_def2(arena, env, scope, def, region);
+
+    let def2_id = env.pool.add(def2);
+
+    let mut mark_node_pool = SlowPool::default();
+
+    let def2_markup_id = def2_to_markup(
+        env,
+        env.pool.get(def2_id),
+        def2_id,
+        &mut mark_node_pool,
+        interns,
+    )?;
+
+    let def2_markup_node = mark_node_pool.get(def2_markup_id);
+
+    mark_node_to_html(def2_markup_node, &mark_node_pool, buf);
+
+    Ok(())
+}

docs/src/expr.rs

@@ -0,0 +1,73 @@
+use crate::html::mark_node_to_html;
+use bumpalo::{collections::String as BumpString, Bump};
+use roc_ast::{
+    ast_error::ASTResult,
+    lang::{self, core::expr::expr_to_expr2::expr_to_expr2},
+    mem_pool::pool::Pool,
+};
+use roc_code_markup::{markup::nodes::expr2_to_markup, slow_pool::SlowPool};
+use roc_module::symbol::{IdentIds, Interns, ModuleId, ModuleIds};
+use roc_parse::ast::Expr;
+use roc_region::all::Region;
+use roc_types::subs::VarStore;
+
+// html is written to buf
+pub fn expr_to_html<'a>(
+    buf: &mut BumpString<'a>,
+    expr: Expr<'a>,
+    env_module_id: ModuleId,
+    env_module_ids: &'a ModuleIds,
+    interns: &Interns,
+) {
+    let mut env_pool = Pool::with_capacity(1024);
+    let env_arena = Bump::new();
+
+    let mut var_store = VarStore::default();
+    let dep_idents = IdentIds::exposed_builtins(8);
+    let exposed_ident_ids = IdentIds::default();
+
+    let mut env = lang::env::Env::new(
+        env_module_id,
+        &env_arena,
+        &mut env_pool,
+        &mut var_store,
+        dep_idents,
+        env_module_ids,
+        exposed_ident_ids,
+    );
+
+    let mut scope = lang::scope::Scope::new(env.home, env.pool, env.var_store);
+    let region = Region::new(0, 0, 0, 0);
+
+    // TODO remove unwrap
+    write_expr_to_bump_str_html(&mut env, &mut scope, region, &expr, interns, buf).unwrap();
+}
+
+fn write_expr_to_bump_str_html<'a, 'b>(
+    env: &mut lang::env::Env<'a>,
+    scope: &mut lang::scope::Scope,
+    region: Region,
+    expr: &'a Expr,
+    interns: &Interns,
+    buf: &mut BumpString<'b>,
+) -> ASTResult<()> {
+    let (expr2, _) = expr_to_expr2(env, scope, expr, region);
+
+    let expr2_id = env.pool.add(expr2);
+
+    let mut mark_node_pool = SlowPool::default();
+
+    let expr2_markup_id = expr2_to_markup(
+        env,
+        env.pool.get(expr2_id),
+        expr2_id,
+        &mut mark_node_pool,
+        interns,
+    )?;
+
+    let expr2_markup_node = mark_node_pool.get(expr2_markup_id);
+
+    mark_node_to_html(expr2_markup_node, &mark_node_pool, buf);
+
+    Ok(())
+}

docs/src/html.rs

@@ -0,0 +1,80 @@
+use bumpalo::collections::String as BumpString;
+use roc_code_markup::{markup::nodes::MarkupNode, slow_pool::SlowPool};
+
+// determine appropriate css class for MarkupNode
+pub fn mark_node_to_html<'a>(
+    mark_node: &MarkupNode,
+    mark_node_pool: &SlowPool,
+    buf: &mut BumpString<'a>,
+) {
+    let additional_newlines: usize;
+
+    match mark_node {
+        MarkupNode::Nested {
+            children_ids,
+            newlines_at_end,
+            ..
+        } => {
+            for &child_id in children_ids {
+                mark_node_to_html(mark_node_pool.get(child_id), mark_node_pool, buf)
+            }
+
+            additional_newlines = *newlines_at_end;
+        }
+        MarkupNode::Text {
+            content,
+            syn_high_style,
+            newlines_at_end,
+            ..
+        } => {
+            use roc_code_markup::syntax_highlight::HighlightStyle::*;
+
+            let css_class = match syn_high_style {
+                Operator => "operator",
+                Comma => "comma",
+                String => "string",
+                FunctionName => "function_name",
+                Type => "type",
+                Bracket => "bracket",
+                Number => "number",
+                PackageRelated => "package-related",
+                Variable => "variable",
+                RecordField => "recordfield",
+                Import => "import",
+                Provides => "provides",
+                Blank => "blank",
+            };
+
+            write_html_to_buf(content, css_class, buf);
+
+            additional_newlines = *newlines_at_end;
+        }
+        MarkupNode::Blank {
+            newlines_at_end, ..
+        } => {
+            let mut content_str = " ".to_string();
+
+            for _ in 0..*newlines_at_end {
+                content_str.push('\n');
+            }
+
+            write_html_to_buf(&content_str, "blank", buf);
+
+            additional_newlines = *newlines_at_end;
+        }
+    }
+
+    for _ in 0..additional_newlines {
+        buf.push('\n')
+    }
+}
+
+fn write_html_to_buf<'a>(content: &str, css_class: &'static str, buf: &mut BumpString<'a>) {
+    let opening_tag: String = ["<span class=\"syntax-", css_class, "\">"].concat();
+
+    buf.push_str(opening_tag.as_str());
+
+    buf.push_str(content);
+
+    buf.push_str("</span>");
+}

docs/src/lib.rs

@@ -1,6 +1,8 @@
 extern crate pulldown_cmark;
 extern crate roc_load;
-use bumpalo::Bump;
+use bumpalo::{collections::String as BumpString, collections::Vec as BumpVec, Bump};
+use def::defs_to_html;
+use expr::expr_to_html;
 use roc_builtins::std::StdLib;
 use roc_can::builtins::builtin_defs_map;
 use roc_can::scope::Scope;
@@ -9,15 +11,19 @@ use roc_load::docs::DocEntry::DocDef;
 use roc_load::docs::{DocEntry, TypeAnnotation};
 use roc_load::docs::{ModuleDocumentation, RecordField};
 use roc_load::file::{LoadedModule, LoadingProblem};
-use roc_module::symbol::{IdentIds, Interns, ModuleId};
+use roc_module::symbol::{IdentIds, Interns, ModuleId, ModuleIds};
 use roc_parse::ident::{parse_ident, Ident};
-use roc_parse::parser::State;
+use roc_parse::parser::{State, SyntaxError};
 use roc_region::all::Region;
 use std::fs;
 use std::path::{Path, PathBuf};
 
-pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
+mod def;
-    let files_docs = files_to_documentations(filenames, std_lib);
+mod expr;
+mod html;
+
+pub fn generate_docs_html(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
+    let loaded_modules = load_modules_for_files(filenames, std_lib);
     let mut arena = Bump::new();
 
     //
@@ -26,7 +32,7 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
         name: "roc/builtins".to_string(),
         version: "1.0.0".to_string(),
         docs: "Package introduction or README.".to_string(),
-        modules: files_docs,
+        modules: loaded_modules,
     };
 
     if !build_dir.exists() {
@@ -53,11 +59,11 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
     .expect("TODO gracefully handle failing to make the favicon");
 
     let template_html = include_str!("./static/index.html")
-        .replace("<!-- search.js -->", &format!("{}search.js", base_href()))
+        .replace("<!-- search.js -->", &format!("{}search.js", base_url()))
-        .replace("<!-- styles.css -->", &format!("{}styles.css", base_href()))
+        .replace("<!-- styles.css -->", &format!("{}styles.css", base_url()))
         .replace(
             "<!-- favicon.svg -->",
-            &format!("{}favicon.svg", base_href()),
+            &format!("{}favicon.svg", base_url()),
         )
         .replace(
             "<!-- Module links -->",
@@ -79,8 +85,8 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
     for loaded_module in package.modules.iter_mut() {
         arena.reset();
 
-        let mut exports: bumpalo::collections::Vec<&str> =
+        let mut exports: BumpVec<&str> =
-            bumpalo::collections::Vec::with_capacity_in(loaded_module.exposed_values.len(), &arena);
+            BumpVec::with_capacity_in(loaded_module.exposed_values.len(), &arena);
 
         // TODO should this also include exposed_aliases?
         for symbol in loaded_module.exposed_values.iter() {
@@ -89,8 +95,8 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
 
         let exports = exports.into_bump_slice();
 
-        for module in loaded_module.documentation.values_mut() {
+        for module_docs in loaded_module.documentation.values() {
-            let module_dir = build_dir.join(module.name.replace(".", "/").as_str());
+            let module_dir = build_dir.join(module_docs.name.replace(".", "/").as_str());
 
             fs::create_dir_all(&module_dir)
                 .expect("TODO gracefully handle not being able to create the module dir");
@@ -103,14 +109,7 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
                 )
                 .replace(
                     "<!-- Module Docs -->",
-                    render_main_content(
+                    render_module_documentation(exports, module_docs, loaded_module).as_str(),
-                        loaded_module.module_id,
-                        exports,
-                        &loaded_module.dep_idents,
-                        &loaded_module.interns,
-                        module,
-                    )
-                    .as_str(),
                 );
 
             fs::write(module_dir.join("index.html"), rendered_module)
@@ -121,20 +120,63 @@ pub fn generate(filenames: Vec<PathBuf>, std_lib: StdLib, build_dir: &Path) {
     println!("🎉 Docs generated in {}", build_dir.display());
 }
 
-fn render_main_content(
+// converts plain-text code to highlighted html
-    home: ModuleId,
+pub fn syntax_highlight_expr<'a>(
-    exposed_values: &[&str],
+    arena: &'a Bump,
-    dep_idents: &MutMap<ModuleId, IdentIds>,
+    buf: &mut BumpString<'a>,
+    code_str: &'a str,
+    env_module_id: ModuleId,
+    env_module_ids: &'a ModuleIds,
     interns: &Interns,
-    module: &mut ModuleDocumentation,
+) -> Result<String, SyntaxError<'a>> {
+    let trimmed_code_str = code_str.trim_end().trim();
+    let state = State::new(trimmed_code_str.as_bytes());
+
+    match roc_parse::expr::test_parse_expr(0, arena, state) {
+        Ok(loc_expr) => {
+            expr_to_html(buf, loc_expr.value, env_module_id, env_module_ids, interns);
+
+            Ok(buf.to_string())
+        }
+        Err(fail) => Err(SyntaxError::Expr(fail)),
+    }
+}
+
+// converts plain-text code to highlighted html
+pub fn syntax_highlight_top_level_defs<'a>(
+    arena: &'a Bump,
+    buf: &mut BumpString<'a>,
+    code_str: &'a str,
+    env_module_id: ModuleId,
+    env_module_ids: &'a ModuleIds,
+    interns: &Interns,
+) -> Result<String, SyntaxError<'a>> {
+    let trimmed_code_str = code_str.trim_end().trim();
+
+    match roc_parse::test_helpers::parse_defs_with(arena, trimmed_code_str) {
+        Ok(vec_loc_def) => {
+            let vec_def = vec_loc_def.iter().map(|loc| loc.value).collect();
+
+            defs_to_html(buf, vec_def, env_module_id, env_module_ids, interns);
+
+            Ok(buf.to_string())
+        }
+        Err(err) => Err(err),
+    }
+}
+
+fn render_module_documentation(
+    exposed_values: &[&str],
+    module: &ModuleDocumentation,
+    loaded_module: &LoadedModule,
 ) -> String {
     let mut buf = String::new();
 
     buf.push_str(
-        html_node(
+        html_to_string(
             "h2",
             vec![("class", "module-name")],
-            html_node("a", vec![("href", "/#")], module.name.as_str()).as_str(),
+            html_to_string("a", vec![("href", "/#")], module.name.as_str()).as_str(),
         )
         .as_str(),
     );
@@ -158,7 +200,9 @@ fn render_main_content(
 
                     let mut content = String::new();
 
-                    content.push_str(html_node("a", vec![("href", href.as_str())], name).as_str());
+                    content.push_str(
+                        html_to_string("a", vec![("href", href.as_str())], name).as_str(),
+                    );
 
                     for type_var in &doc_def.type_vars {
                         content.push(' ');
@@ -177,7 +221,7 @@ fn render_main_content(
                     type_annotation_to_html(0, &mut content, type_ann);
 
                     buf.push_str(
-                        html_node(
+                        html_to_string(
                             "h3",
                             vec![("id", name), ("class", "entry-name")],
                             content.as_str(),
@@ -188,12 +232,10 @@ fn render_main_content(
                     if let Some(docs) = &doc_def.docs {
                         buf.push_str(
                             markdown_to_html(
-                                home,
                                 exposed_values,
-                                dep_idents,
+                                &module.scope,
-                                &mut module.scope,
-                                interns,
                                 docs.to_string(),
+                                loaded_module,
                             )
                             .as_str(),
                         );
@@ -201,12 +243,10 @@ fn render_main_content(
                 }
                 DocEntry::DetachedDoc(docs) => {
                     let markdown = markdown_to_html(
-                        home,
                         exposed_values,
-                        dep_idents,
+                        &module.scope,
-                        &mut module.scope,
-                        interns,
                         docs.to_string(),
+                        loaded_module,
                     );
                     buf.push_str(markdown.as_str());
                 }
@@ -217,7 +257,7 @@ fn render_main_content(
     buf
 }
 
-fn html_node(tag_name: &str, attrs: Vec<(&str, &str)>, content: &str) -> String {
+fn html_to_string(tag_name: &str, attrs: Vec<(&str, &str)>, content: &str) -> String {
     let mut buf = String::new();
 
     buf.push('<');
@@ -246,62 +286,62 @@ fn html_node(tag_name: &str, attrs: Vec<(&str, &str)>, content: &str) -> String
     buf
 }
 
-fn base_href() -> String {
+fn base_url() -> String {
     // e.g. "builtins/" in "https://roc-lang.org/builtins/Str"
     //
     // TODO make this a CLI flag to the `docs` subcommand instead of an env var
     match std::env::var("ROC_DOCS_URL_ROOT") {
         Ok(root_builtins_path) => {
-            let mut href = String::with_capacity(root_builtins_path.len() + 64);
+            let mut url_str = String::with_capacity(root_builtins_path.len() + 64);
 
             if !root_builtins_path.starts_with('/') {
-                href.push('/');
+                url_str.push('/');
             }
 
-            href.push_str(&root_builtins_path);
+            url_str.push_str(&root_builtins_path);
 
             if !root_builtins_path.ends_with('/') {
-                href.push('/');
+                url_str.push('/');
             }
 
-            href
+            url_str
         }
         _ => {
-            let mut href = String::with_capacity(64);
+            let mut url_str = String::with_capacity(64);
 
-            href.push('/');
+            url_str.push('/');
 
-            href
+            url_str
         }
     }
 }
 
 fn render_name_and_version(name: &str, version: &str) -> String {
     let mut buf = String::new();
-    let mut href = base_href();
+    let mut url_str = base_url();
 
-    href.push_str(name);
+    url_str.push_str(name);
 
     buf.push_str(
-        html_node(
+        html_to_string(
             "h1",
             vec![("class", "pkg-full-name")],
-            html_node("a", vec![("href", href.as_str())], name).as_str(),
+            html_to_string("a", vec![("href", url_str.as_str())], name).as_str(),
         )
         .as_str(),
     );
 
-    let mut versions_href = base_href();
+    let mut versions_url_str = base_url();
 
-    versions_href.push('/');
+    versions_url_str.push('/');
-    versions_href.push_str(name);
+    versions_url_str.push_str(name);
-    versions_href.push('/');
+    versions_url_str.push('/');
-    versions_href.push_str(version);
+    versions_url_str.push_str(version);
 
     buf.push_str(
-        html_node(
+        html_to_string(
             "a",
-            vec![("class", "version"), ("href", versions_href.as_str())],
+            vec![("class", "version"), ("href", versions_url_str.as_str())],
             version,
         )
         .as_str(),
@@ -321,13 +361,13 @@ fn render_sidebar<'a, I: Iterator<Item = (Vec<String>, &'a ModuleDocumentation)>
         let name = module.name.as_str();
 
         let href = {
-            let mut href_buf = base_href();
+            let mut href_buf = base_url();
             href_buf.push_str(name);
             href_buf
         };
 
         sidebar_entry_content.push_str(
-            html_node(
+            html_to_string(
                 "a",
                 vec![("class", "sidebar-module-link"), ("href", href.as_str())],
                 name,
@@ -348,7 +388,7 @@ fn render_sidebar<'a, I: Iterator<Item = (Vec<String>, &'a ModuleDocumentation)>
                         entry_href.push_str(doc_def.name.as_str());
 
                         entries_buf.push_str(
-                            html_node(
+                            html_to_string(
                                 "a",
                                 vec![("href", entry_href.as_str())],
                                 doc_def.name.as_str(),
@@ -363,7 +403,7 @@ fn render_sidebar<'a, I: Iterator<Item = (Vec<String>, &'a ModuleDocumentation)>
         };
 
         sidebar_entry_content.push_str(
-            html_node(
+            html_to_string(
                 "div",
                 vec![("class", "sidebar-sub-entries")],
                 entries.as_str(),
@@ -372,7 +412,7 @@ fn render_sidebar<'a, I: Iterator<Item = (Vec<String>, &'a ModuleDocumentation)>
         );
 
         buf.push_str(
-            html_node(
+            html_to_string(
                 "div",
                 vec![("class", "sidebar-entry")],
                 sidebar_entry_content.as_str(),
@@ -384,9 +424,9 @@ fn render_sidebar<'a, I: Iterator<Item = (Vec<String>, &'a ModuleDocumentation)>
     buf
 }
 
-pub fn files_to_documentations(filenames: Vec<PathBuf>, std_lib: StdLib) -> Vec<LoadedModule> {
+pub fn load_modules_for_files(filenames: Vec<PathBuf>, std_lib: StdLib) -> Vec<LoadedModule> {
     let arena = Bump::new();
-    let mut files_docs = vec![];
+    let mut modules = vec![];
 
     for filename in filenames {
         let mut src_dir = filename.clone();
@@ -401,7 +441,7 @@ pub fn files_to_documentations(filenames: Vec<PathBuf>, std_lib: StdLib) -> Vec<
             std::mem::size_of::<usize>() as u32, // This is just type-checking for docs, so "target" doesn't matter
             builtin_defs_map,
         ) {
-            Ok(loaded) => files_docs.push(loaded),
+            Ok(loaded) => modules.push(loaded),
             Err(LoadingProblem::FormattedReport(report)) => {
                 println!("{}", report);
                 panic!();
@@ -410,7 +450,7 @@ pub fn files_to_documentations(filenames: Vec<PathBuf>, std_lib: StdLib) -> Vec<
         }
     }
 
-    files_docs
+    modules
 }
 
 const INDENT: &str = "    ";
@@ -425,6 +465,7 @@ fn new_line(buf: &mut String) {
     buf.push('\n');
 }
 
+// html is written to buf
 fn type_annotation_to_html(indent_level: usize, buf: &mut String, type_ann: &TypeAnnotation) {
     let is_multiline = should_be_multiline(type_ann);
     match type_ann {
@@ -686,7 +727,7 @@ fn doc_url<'a>(
     home: ModuleId,
     exposed_values: &[&str],
     dep_idents: &MutMap<ModuleId, IdentIds>,
-    scope: &mut Scope,
+    scope: &Scope,
     interns: &'a Interns,
     mut module_name: &'a str,
     ident: &str,
@@ -753,7 +794,7 @@ fn doc_url<'a>(
         }
     }
 
-    let mut url = base_href();
+    let mut url = base_url();
 
     // Example:
     //
@@ -769,12 +810,10 @@ fn doc_url<'a>(
 }
 
 fn markdown_to_html(
-    home: ModuleId,
     exposed_values: &[&str],
-    dep_idents: &MutMap<ModuleId, IdentIds>,
+    scope: &Scope,
-    scope: &mut Scope,
-    interns: &Interns,
     markdown: String,
+    loaded_module: &LoadedModule,
 ) -> String {
     use pulldown_cmark::{BrokenLink, CodeBlockKind, CowStr, Event, LinkType, Tag::*};
 
@@ -801,11 +840,11 @@ fn markdown_to_html(
                         match iter.next() {
                             Some(symbol_name) if iter.next().is_none() => {
                                 let DocUrl { url, title } = doc_url(
-                                    home,
+                                    loaded_module.module_id,
                                     exposed_values,
-                                    dep_idents,
+                                    &loaded_module.dep_idents,
                                     scope,
-                                    interns,
+                                    &loaded_module.interns,
                                     module_name,
                                     symbol_name,
                                 );
@@ -824,11 +863,11 @@ fn markdown_to_html(
                         // This looks like a global tag name, but it could
                         // be a type alias that's in scope, e.g. [I64]
                         let DocUrl { url, title } = doc_url(
-                            home,
+                            loaded_module.module_id,
                             exposed_values,
-                            dep_idents,
+                            &loaded_module.dep_idents,
                             scope,
-                            interns,
+                            &loaded_module.interns,
                             "",
                             type_name,
                         );
@@ -843,6 +882,9 @@ fn markdown_to_html(
     };
 
     let markdown_options = pulldown_cmark::Options::empty();
+
+    let mut expecting_code_block = false;
+
     let mut docs_parser = vec![];
     let (_, _) = pulldown_cmark::Parser::new_with_broken_link_callback(
         &markdown,
@@ -850,6 +892,7 @@ fn markdown_to_html(
         Some(&mut broken_link_callback),
     )
     .fold((0, 0), |(start_quote_count, end_quote_count), event| {
+
         match &event {
             // Replace this sequence (`>>>` syntax):
             //     Start(BlockQuote)
@@ -915,6 +958,39 @@ fn markdown_to_html(
 
                 (start_quote_count, end_quote_count)
             }
+            Event::Start(CodeBlock(CodeBlockKind::Fenced(_))) => {
+                expecting_code_block = true;
+                docs_parser.push(event);
+                (0, 0)
+            }
+            Event::End(CodeBlock(_)) => {
+                expecting_code_block = false;
+                docs_parser.push(event);
+                (0, 0)
+            }
+            Event::Text(CowStr::Borrowed(code_str)) if expecting_code_block => {
+                let code_block_arena = Bump::new();
+
+                let mut code_block_buf = BumpString::new_in(&code_block_arena);
+                match syntax_highlight_expr(
+                    &code_block_arena,
+                    &mut code_block_buf,
+                    code_str,
+                    loaded_module.module_id,
+                    &loaded_module.interns.module_ids,
+                    &loaded_module.interns
+                )
+                {
+                    Ok(highlighted_code_str) => {
+                        docs_parser.push(Event::Html(CowStr::from(highlighted_code_str)));
+                    }
+                    Err(syntax_error) => {
+                        panic!("Unexpected parse failure when parsing this for rendering in docs:\n\n{}\n\nParse error was:\n\n{:?}\n\n", code_str, syntax_error)
+                    }
+                };
+
+                (0, 0)
+            }
             _ => {
                 docs_parser.push(event);
                 (0, 0)

docs/src/static/index.html

@@ -41,7 +41,7 @@
 </main>
 <footer>
     <p>Made by people who like to make nice things.</p>
-    <p>© 2020</p>
+    <p>© 2021</p>
 </footer>
 </body>
 

docs/src/static/styles.css

@@ -7,7 +7,6 @@
   --body-bg-color: #fdfdfd;
   --border-color: #e9e9e9;
   --faded-color: #4c4c4c;
-  --monospace-font;
   --font-sans: -apple-system, BlinkMacSystemFont, Roboto, Helvetica, Arial, sans-serif;
   --font-mono: SFMono-Regular, Consolas, "Liberation Mono", Menlo, Courier, monospace;
   --top-header-height: 67px;
@@ -283,7 +282,6 @@ code {
   font-family: var(--font-mono);
   color: var(--code-color);
   background-color: var(--code-bg-color);
-  padding: 2px 8px;
   display: inline-block;
 }
 
@@ -306,15 +304,34 @@ pre {
   overflow-x: auto;
 }
 
-pre code {
-  padding: 6px 8px;
-}
-
 .hidden {
   /* Use !important to win all specificity fights. */
   display: none !important;
 }
 
+.syntax-number {
+    color: #60B7BF;
+}
+.syntax-string {
+  color:#F7577C;
+}
+
+.syntax-bracket {
+  color:#FF335F;
+}
+.syntax-closure-dash,
+.syntax-closure-arrow,
+.syntax-operator
+{
+    color: #ffffff;
+}
+.syntax-comma {
+  color: #9573E6;
+}
+.syntax-comment {
+  color: #ff0000;
+}
+
 #module-search:placeholder-shown {
   padding: 0;
   opacity: 0;

docs/tests/insert_syntax_highlighting.rs

@@ -0,0 +1,158 @@
+#[macro_use]
+extern crate pretty_assertions;
+
+#[cfg(test)]
+mod insert_doc_syntax_highlighting {
+    use std::{fs::File, io::Write, path::PathBuf};
+
+    use bumpalo::{collections::String as BumpString, Bump};
+    use roc_ast::module::load_module;
+    use roc_docs::{syntax_highlight_expr, syntax_highlight_top_level_defs};
+    use roc_load::file::LoadedModule;
+    use tempfile::tempdir;
+    use uuid::Uuid;
+
+    fn expect_html(code_str: &str, want: &str, use_expr: bool) {
+        let loaded_module = make_mock_module();
+
+        let code_block_arena = Bump::new();
+        let mut code_block_buf = BumpString::new_in(&code_block_arena);
+
+        if use_expr {
+            match syntax_highlight_expr(
+                &code_block_arena,
+                &mut code_block_buf,
+                code_str,
+                loaded_module.module_id,
+                &loaded_module.interns.module_ids,
+                &loaded_module.interns,
+            ) {
+                Ok(highlighted_code_str) => {
+                    assert_eq!(highlighted_code_str, want);
+                }
+                Err(syntax_error) => {
+                    panic!("Unexpected parse failure when parsing this for rendering in docs:\n\n{}\n\nParse error was:\n\n{:?}\n\n", code_str, syntax_error)
+                }
+            };
+        } else {
+            match syntax_highlight_top_level_defs(
+                &code_block_arena,
+                &mut code_block_buf,
+                code_str,
+                loaded_module.module_id,
+                &loaded_module.interns.module_ids,
+                &loaded_module.interns,
+            ) {
+                Ok(highlighted_code_str) => {
+                    assert_eq!(highlighted_code_str, want);
+                }
+                Err(syntax_error) => {
+                    panic!("Unexpected parse failure when parsing this for rendering in docs:\n\n{}\n\nParse error was:\n\n{:?}\n\n", code_str, syntax_error)
+                }
+            };
+        }
+    }
+
+    pub const HELLO_WORLD: &str = r#"
+app "test-app"
+    packages { base: "platform" }
+    imports []
+    provides [ main ] to base
+
+main = "Hello, world!"
+
+
+"#;
+
+    fn make_mock_module() -> LoadedModule {
+        let temp_dir = tempdir().expect("Failed to create temporary directory for test.");
+        let temp_file_path_buf =
+            PathBuf::from([Uuid::new_v4().to_string(), ".roc".to_string()].join(""));
+        let temp_file_full_path = temp_dir.path().join(temp_file_path_buf);
+
+        let mut file = File::create(temp_file_full_path.clone()).expect(&format!(
+            "Failed to create temporary file for path {:?}",
+            temp_file_full_path
+        ));
+        writeln!(file, "{}", HELLO_WORLD).expect(&format!(
+            "Failed to write {:?} to file: {:?}",
+            HELLO_WORLD, file
+        ));
+
+        load_module(&temp_file_full_path)
+    }
+
+    fn expect_html_expr(code_str: &str, want: &str) {
+        expect_html(code_str, want, true)
+    }
+
+    fn expect_html_def(code_str: &str, want: &str) {
+        expect_html(code_str, want, false)
+    }
+
+    #[test]
+    fn number_expr() {
+        expect_html_expr("2", r#"<span class="syntax-number">2</span>"#);
+    }
+
+    #[test]
+    fn string_expr() {
+        expect_html_expr(r#""abc""#, r#"<span class="syntax-string">"abc"</span>"#);
+    }
+
+    #[test]
+    fn empty_list_expr() {
+        expect_html_expr(
+            r#"[]"#,
+            r#"<span class="syntax-bracket">[ </span><span class="syntax-bracket"> ]</span>"#,
+        );
+    }
+
+    #[test]
+    fn single_elt_list_expr() {
+        expect_html_expr(
+            r#"[ 0 ]"#,
+            r#"<span class="syntax-bracket">[ </span><span class="syntax-number">0</span><span class="syntax-bracket"> ]</span>"#,
+        );
+    }
+
+    #[test]
+    fn multi_elt_list_expr() {
+        expect_html_expr(
+            r#"[ "hello", "WoRlD" ]"#,
+            r#"<span class="syntax-bracket">[ </span><span class="syntax-string">"hello"</span><span class="syntax-comma">, </span><span class="syntax-string">"WoRlD"</span><span class="syntax-bracket"> ]</span>"#,
+        );
+    }
+
+    #[test]
+    fn record_expr() {
+        expect_html_expr(
+            r#"{ a: "hello!" }"#,
+            "<span class=\"syntax-bracket\">{ </span><span class=\"syntax-recordfield\">a</span><span class=\"syntax-operator\">: </span><span class=\"syntax-string\">\"hello!\"</span><span class=\"syntax-bracket\"> }</span>",
+        );
+    }
+
+    #[test]
+    fn nested_record_expr() {
+        expect_html_expr(
+            r#"{ a: { bB: "WoRlD" } }"#,
+            "<span class=\"syntax-bracket\">{ </span><span class=\"syntax-recordfield\">a</span><span class=\"syntax-operator\">: </span><span class=\"syntax-bracket\">{ </span><span class=\"syntax-recordfield\">bB</span><span class=\"syntax-operator\">: </span><span class=\"syntax-string\">\"WoRlD\"</span><span class=\"syntax-bracket\"> }</span><span class=\"syntax-bracket\"> }</span>",
+        );
+    }
+
+    #[test]
+    fn top_level_def_value() {
+        expect_html_def(
+            r#"main = "Hello, World!""#,
+            "<span class=\"syntax-variable\">main</span><span class=\"syntax-operator\"> = </span><span class=\"syntax-string\">\"Hello, World!\"</span>\n\n",
+        );
+    }
+
+    #[test]
+    fn tld_list() {
+        expect_html_def(
+            r#"main = [ 1, 2, 3 ]"#,
+            "<span class=\"syntax-variable\">main</span><span class=\"syntax-operator\"> = </span><span class=\"syntax-bracket\">[ </span><span class=\"syntax-number\">1</span><span class=\"syntax-comma\">, </span><span class=\"syntax-number\">2</span><span class=\"syntax-comma\">, </span><span class=\"syntax-number\">3</span><span class=\"syntax-bracket\"> ]</span>\n\n",
+        );
+    }
+}

editor/src/editor/main.rs

@@ -25,10 +25,7 @@ use fs_extra::dir::{copy, ls, CopyOptions, DirEntryAttr, DirEntryValue};
 use pipelines::RectResources;
 use roc_ast::lang::env::Env;
 use roc_ast::mem_pool::pool::Pool;
-use roc_can::builtins::builtin_defs_map;
+use roc_ast::module::load_module;
-use roc_collections::all::MutMap;
-use roc_load;
-use roc_load::file::LoadedModule;
 use roc_module::symbol::IdentIds;
 use roc_types::subs::VarStore;
 use std::collections::HashSet;
@@ -557,40 +554,6 @@ fn copy_roc_platform_if_not_exists(
     }
 }
 
-pub fn load_module(src_file: &Path) -> LoadedModule {
-    let subs_by_module = MutMap::default();
-
-    let arena = Bump::new();
-    let loaded = roc_load::file::load_and_typecheck(
-        &arena,
-        src_file.to_path_buf(),
-        arena.alloc(roc_builtins::std::standard_stdlib()),
-        src_file.parent().unwrap_or_else(|| {
-            panic!(
-                "src_file {:?} did not have a parent directory but I need to have one.",
-                src_file
-            )
-        }),
-        subs_by_module,
-        8,
-        builtin_defs_map,
-    );
-
-    match loaded {
-        Ok(x) => x,
-        Err(roc_load::file::LoadingProblem::FormattedReport(report)) => {
-            panic!(
-                "Failed to load module from src_file {:?}. Report: {:?}",
-                src_file, report
-            );
-        }
-        Err(e) => panic!(
-            "Failed to load module from src_file {:?}: {:?}",
-            src_file, e
-        ),
-    }
-}
-
 fn queue_no_file_text(
     size: &PhysicalSize<u32>,
     text: &str,

editor/src/editor/mvc/ed_model.rs

@@ -63,7 +63,6 @@ pub fn init_model<'a>(
         EmptyCodeString {}.fail()
     } else {
         Ok(ast_to_mark_nodes(
-            code_arena,
             &mut module.env,
             &module.ast,
             &mut mark_node_pool,
@@ -199,7 +198,6 @@ impl<'a> EdModule<'a> {
 #[cfg(test)]
 pub mod test_ed_model {
     use crate::editor::ed_error::EdResult;
-    use crate::editor::main::load_module;
     use crate::editor::mvc::ed_model;
     use crate::editor::resources::strings::HELLO_WORLD;
     use crate::ui::text::caret_w_select::test_caret_w_select::convert_dsl_to_selection;
@@ -212,6 +210,7 @@ pub mod test_ed_model {
     use ed_model::EdModel;
     use roc_ast::lang::env::Env;
     use roc_ast::mem_pool::pool::Pool;
+    use roc_ast::module::load_module;
     use roc_load::file::LoadedModule;
     use roc_module::symbol::IdentIds;
     use roc_module::symbol::ModuleIds;

www/public/styles.css

@@ -282,7 +282,6 @@ code {
   font-family: var(--font-mono);
   color: var(--code-color);
   background-color: var(--code-bg-color);
-  padding: 0 8px;
   display: inline-block;
   line-height: 28px;
 }
@@ -303,15 +302,15 @@ pre {
   overflow-x: auto;
 }
 
-pre code {
-  padding: 6px 8px;
-}
-
 .hidden {
   /* Use !important to win all specificity fights. */
   display: none !important;
 }
 
+.syntax-comment {
+  color: #ff0000;
+}
+
 #module-search:placeholder-shown {
   padding: 0;
   opacity: 0;