diff options
| -rw-r--r-- | tvix/eval/src/compiler/bindings.rs | 206 |
1 files changed, 108 insertions, 98 deletions
diff --git a/tvix/eval/src/compiler/bindings.rs b/tvix/eval/src/compiler/bindings.rs index 6322a1d5247b..b09989bc00e2 100644 --- a/tvix/eval/src/compiler/bindings.rs +++ b/tvix/eval/src/compiler/bindings.rs @@ -34,6 +34,113 @@ struct TrackedBinding { /// AST-traversing functions related to bindings. impl Compiler<'_> { + fn compile_inherits<N>( + &mut self, + slot: LocalIdx, + count: &mut usize, + bindings: &mut Vec<TrackedBinding>, + rec_attrs: bool, + node: &N, + ) where + N: ToSpan + ast::HasEntry, + { + // First pass to find all plain inherits (if they are not useless). + // Since they always resolve to a higher scope, we can just compile and + // declare them immediately. This needs to happen *before* we declare + // any other locals in the scope or the stack order gets messed up. + // While we are looping through the inherits, already note all inherit + // (from) expressions, that may very well resolve recursively and need + // to be compiled like normal let in bindings. + let mut inherit_froms: Vec<(ast::Expr, String, Span)> = vec![]; + for inherit in node.inherits() { + match inherit.from() { + // Within a `let` binding, inheriting from the outer + // scope is a no-op *if* the identifier can be + // statically resolved. + None if !rec_attrs && !self.scope().has_with() => { + self.emit_warning(&inherit, WarningKind::UselessInherit); + continue; + } + + None => { + for attr in inherit.attrs() { + let name = match self.expr_static_attr_str(&attr) { + Some(name) => name, + None => { + self.emit_error(&attr, ErrorKind::DynamicKeyInScope("inherit")); + continue; + } + }; + + *count += 1; + + // If the identifier resolves statically in a + // `let`, it has precedence over dynamic + // bindings, and the inherit is useless. + if !rec_attrs + && matches!( + self.scope_mut().resolve_local(&name), + LocalPosition::Known(_) + ) + { + self.emit_warning(&attr, WarningKind::UselessInherit); + continue; + } + + if rec_attrs { + self.emit_constant(Value::String(SmolStr::new(&name).into()), &attr); + let span = self.span_for(&attr); + self.scope_mut().declare_phantom(span, true); + } + + self.compile_identifier_access(slot, &name, &attr); + let idx = self.declare_local(&attr, &name); + self.scope_mut().mark_initialised(idx); + } + } + + Some(from) => { + for attr in inherit.attrs() { + let name = match self.expr_static_attr_str(&attr) { + Some(name) => name, + None => { + self.emit_error(&attr, ErrorKind::DynamicKeyInScope("inherit")); + continue; + } + }; + + *count += 1; + inherit_froms.push((from.expr().unwrap(), name, self.span_for(&attr))); + } + } + } + } + + // Begin with the inherit (from)s since they all become a thunk anyway + for (from, name, span) in inherit_froms { + let key_slot = if rec_attrs { + Some(KeySlot { + slot: self.scope_mut().declare_phantom(span, false), + name: SmolStr::new(&name), + }) + } else { + None + }; + + let value_slot = self.declare_local(&span, &name); + + bindings.push(TrackedBinding { + key_slot, + value_slot, + binding: Binding::InheritFrom { + namespace: from, + name: SmolStr::new(&name), + span, + }, + }); + } + } + /// Compiles inherited values in an attribute set. Inherited /// values are *always* inherited from the outer scope, even if /// there is a matching name within a recursive attribute set. @@ -276,107 +383,10 @@ impl Compiler<'_> { let mut count = 0; self.scope_mut().begin_scope(); - // First pass to find all plain inherits (if they are not useless). - // Since they always resolve to a higher scope, we can just compile and - // declare them immediately. This needs to happen *before* we declare - // any other locals in the scope or the stack order gets messed up. - // While we are looping through the inherits, already note all inherit - // (from) expressions, that may very well resolve recursively and need - // to be compiled like normal let in bindings. - let mut inherit_froms: Vec<(ast::Expr, String, Span)> = vec![]; - for inherit in node.inherits() { - match inherit.from() { - // Within a `let` binding, inheriting from the outer - // scope is a no-op *if* the identifier can be - // statically resolved. - None if !rec_attrs && !self.scope().has_with() => { - self.emit_warning(&inherit, WarningKind::UselessInherit); - continue; - } - - None => { - for attr in inherit.attrs() { - let name = match self.expr_static_attr_str(&attr) { - Some(name) => name, - None => { - self.emit_error(&attr, ErrorKind::DynamicKeyInScope("inherit")); - continue; - } - }; - - count += 1; - - // If the identifier resolves statically in a - // `let`, it has precedence over dynamic - // bindings, and the inherit is useless. - if !rec_attrs - && matches!( - self.scope_mut().resolve_local(&name), - LocalPosition::Known(_) - ) - { - self.emit_warning(&attr, WarningKind::UselessInherit); - continue; - } - - if rec_attrs { - self.emit_constant(Value::String(SmolStr::new(&name).into()), &attr); - let span = self.span_for(&attr); - self.scope_mut().declare_phantom(span, true); - } - - self.compile_identifier_access(slot, &name, &attr); - let idx = self.declare_local(&attr, &name); - self.scope_mut().mark_initialised(idx); - } - } - - Some(from) => { - for attr in inherit.attrs() { - let name = match self.expr_static_attr_str(&attr) { - Some(name) => name, - None => { - self.emit_error(&attr, ErrorKind::DynamicKeyInScope("inherit")); - continue; - } - }; - - count += 1; - inherit_froms.push((from.expr().unwrap(), name, self.span_for(&attr))); - } - } - } - } - // Vector to track these observed bindings. let mut bindings: Vec<TrackedBinding> = vec![]; - // Begin second pass to ensure that all remaining identifiers - // (that may resolve recursively) are known. - - // Begin with the inherit (from)s since they all become a thunk anyway - for (from, name, span) in inherit_froms { - let key_slot = if rec_attrs { - Some(KeySlot { - slot: self.scope_mut().declare_phantom(span, false), - name: SmolStr::new(&name), - }) - } else { - None - }; - - let value_slot = self.declare_local(&span, &name); - - bindings.push(TrackedBinding { - key_slot, - value_slot, - binding: Binding::InheritFrom { - namespace: from, - name: SmolStr::new(&name), - span, - }, - }); - } + self.compile_inherits(slot, &mut count, &mut bindings, rec_attrs, node); // Declare all regular bindings for entry in node.attrpath_values() { |