nandi.uk
Fork of daniellemaywood.uk/gleam — Wasm codegen work
Fix bug when `let assert` is alone in a block
author
GearsDatapacks
committer
Louis Pilfold
date
(Mar 26, 2025, 10:35 AM UTC)
commit
5da051a9
5da051a9898fe03dc1b21af533929ebde181e340
parent
16e27632
16e2763210f6cc3a69508021182404fefb34afe7
+76
-21
+4
CHANGELOG.md
+4
CHANGELOG.md
···
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when it could use the cache from previous compilations.
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([Louis Pilfold](https://github.com/lpil))
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- Fixed a bug where `let assert` would not assert that the given value matched
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the pattern if it was the only expression inside a block.
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([Surya Rose](https://github.com/GearsDatapacks))
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## v1.9.1 - 2025-03-10
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### Formatter
+26
-21
compiler-core/src/javascript/expression.rs
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-21
compiler-core/src/javascript/expression.rs
···
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fn block(&mut self, statements: &'a Vec1<TypedStatement>) -> Output<'a> {
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if statements.len() == 1 {
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match statements.first() {
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Statement::Expression(expression) => self.child_expression(expression),
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Statement::Expression(expression) => return self.child_expression(expression),
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Statement::Assignment(assignment) => {
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self.child_expression(assignment.value.as_ref())
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}
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Statement::Assignment(assignment) => match &assignment.kind {
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AssignmentKind::Let | AssignmentKind::Generated => {
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return self.child_expression(assignment.value.as_ref());
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}
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// We can't just return the right-hand side of a `let assert`
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// assignment; we still need to check that the pattern matches.
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AssignmentKind::Assert { .. } => {}
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},
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Statement::Use(use_) => self.child_expression(&use_.call),
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Statement::Use(use_) => return self.child_expression(&use_.call),
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}
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} else {
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match &self.scope_position {
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Position::Tail | Position::Assign(_) => self.block_document(statements),
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Position::NotTail(Ordering::Strict) => self
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.immediately_invoked_function_expression(statements, |this, statements| {
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this.statements(statements)
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}),
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Position::NotTail(Ordering::Loose) => self.wrap_block(|this| {
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// Save previous scope
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let current_scope_vars = this.current_scope_vars.clone();
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}
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match &self.scope_position {
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Position::Tail | Position::Assign(_) => self.block_document(statements),
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Position::NotTail(Ordering::Strict) => self
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.immediately_invoked_function_expression(statements, |this, statements| {
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this.statements(statements)
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}),
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Position::NotTail(Ordering::Loose) => self.wrap_block(|this| {
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// Save previous scope
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let current_scope_vars = this.current_scope_vars.clone();
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let document = this.block_document(statements)?;
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let document = this.block_document(statements)?;
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// Restore previous state
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this.current_scope_vars = current_scope_vars;
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// Restore previous state
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this.current_scope_vars = current_scope_vars;
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Ok(document)
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}),
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}
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Ok(document)
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}),
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}
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}
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+14
compiler-core/src/javascript/tests/blocks.rs
+14
compiler-core/src/javascript/tests/blocks.rs
+32
compiler-core/src/javascript/tests/snapshots/gleam_core__javascript__tests__blocks__let_assert_only_statement_in_block.snap
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compiler-core/src/javascript/tests/snapshots/gleam_core__javascript__tests__blocks__let_assert_only_statement_in_block.snap
···
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---
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source: compiler-core/src/javascript/tests/blocks.rs
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expression: "\npub fn main() {\n {\n let assert Ok(1) = Error(Nil)\n }\n}\n"
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---
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----- SOURCE CODE
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pub fn main() {
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{
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let assert Ok(1) = Error(Nil)
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}
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}
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----- COMPILED JAVASCRIPT
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import { Error, makeError } from "../gleam.mjs";
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export function main() {
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{
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let $ = new Error(undefined);
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if (!$.isOk() || $[0] !== 1) {
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throw makeError(
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"let_assert",
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"my/mod",
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4,
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"main",
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"Pattern match failed, no pattern matched the value.",
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{ value: $ }
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)
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}
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return $;
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}
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}