lisette-emit 0.2.2

Little language inspired by Rust that compiles to Go
Documentation
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mod bindings;
pub(crate) mod calls;
mod collectors;
pub(crate) mod control_flow;
pub(crate) mod definitions;
pub(crate) mod expressions;
pub mod imports;
pub(crate) mod names;
mod output;
pub(crate) mod patterns;
pub(crate) mod queries;
pub(crate) mod statements;
pub(crate) mod types;
mod utils;

pub(crate) use bindings::Bindings;
pub(crate) use calls::go_interop::GoCallStrategy;
pub(crate) use definitions::enum_layout::EnumLayout;
pub(crate) use names::go_name;
pub(crate) use names::go_name::escape_reserved;
pub(crate) use output::OutputCollector;
pub(crate) use types::emitter::{ArmPosition, EmitFlags, LineIndex, LoopContext, Position};
pub(crate) use types::prelude::PreludeType;
pub(crate) use utils::is_order_sensitive;
pub(crate) use utils::write_line;

pub use names::go_name::PRELUDE_IMPORT_PATH;
pub use output::OutputFile;

use rustc_hash::{FxHashMap as HashMap, FxHashSet as HashSet};
use std::sync::Arc;

use ecow::EcoString;
use imports::ImportBuilder;
use syntax::ast::{Generic, Span};
use syntax::program::{
    Definition, DefinitionBody, EmitInput, File, ModuleId, MutationInfo, UnusedInfo,
};
use syntax::types::{Symbol, Type};

#[derive(Clone, Debug, Default)]
pub struct EmitOptions {
    pub debug: bool,
}

#[derive(Default)]
pub(crate) struct GlobalEmitData {
    pub(crate) go_call_strategies: HashMap<String, GoCallStrategy>,
    pub(crate) exported_method_names: HashSet<String>,
    pub(crate) make_function_names: HashMap<String, String>,
}

impl GlobalEmitData {
    fn compute(definitions: &HashMap<Symbol, Definition>) -> Self {
        let mut globals = GlobalEmitData::default();

        for prelude_type in PreludeType::enum_types() {
            for (constructor, make_fn) in prelude_type.make_function_entries() {
                globals.make_function_names.insert(constructor, make_fn);
            }
        }

        for (key, definition) in definitions.iter() {
            let is_go = go_name::is_go_import(key);

            if is_go
                && let Type::Function { return_type, .. } = match definition.ty() {
                    Type::Forall { body, .. } => body.as_ref(),
                    other => other,
                }
                && let Some(strategy) =
                    classify_go_return_type(definitions, return_type, definition.go_hints())
            {
                globals.go_call_strategies.insert(key.to_string(), strategy);
            }

            match &definition.body {
                DefinitionBody::Interface {
                    definition: iface, ..
                } if definition.visibility.is_public() => {
                    for method_name in iface.methods.keys() {
                        globals
                            .exported_method_names
                            .insert(method_name.to_string());
                    }
                }
                DefinitionBody::Value { .. }
                    if definition.visibility.is_public()
                        && !is_go
                        && !key.starts_with(go_name::PRELUDE_PREFIX)
                        && key.chars().filter(|c| *c == '.').count() >= 2 =>
                {
                    let method_name = go_name::unqualified_name(key);
                    globals
                        .exported_method_names
                        .insert(method_name.to_string());
                }
                _ => {}
            }

            if let Definition {
                name: Some(name),
                body: DefinitionBody::Enum { variants, .. },
                ..
            } = definition
                && PreludeType::from_name(name).is_none()
            {
                for (constructor, make_fn) in user_enum_make_function_entries(name, variants) {
                    globals.make_function_names.insert(constructor, make_fn);
                }
            }
        }

        globals
    }
}

/// Make-function name registry entries for a user-declared enum, paralleling
/// [`PreludeType::make_function_entries`].
pub(crate) fn user_enum_make_function_entries<'a>(
    name: &'a str,
    variants: &'a [syntax::ast::EnumVariant],
) -> impl Iterator<Item = (String, String)> + 'a {
    let go_type_name = go_name::escape_keyword(name).into_owned();
    variants.iter().map(move |variant| {
        let constructor = format!("{}.{}", name, variant.name);
        let make_fn = format!("Make{}{}", go_type_name, variant.name);
        (constructor, make_fn)
    })
}

pub(crate) fn classify_go_return_type(
    definitions: &HashMap<Symbol, Definition>,
    return_ty: &Type,
    go_hints: &[String],
) -> Option<GoCallStrategy> {
    if return_ty.is_partial() {
        return Some(GoCallStrategy::Partial);
    }
    if return_ty.is_result() {
        return Some(GoCallStrategy::Result);
    }
    if return_ty.is_option() {
        if let Some(value) = sentinel_hint(go_hints) {
            return Some(GoCallStrategy::Sentinel { value });
        }
        if !is_nullable_option(definitions, return_ty) {
            return Some(GoCallStrategy::CommaOk);
        }
        if go_hints.iter().any(|s| s == "comma_ok") {
            return Some(GoCallStrategy::CommaOk);
        }
        return Some(GoCallStrategy::NullableReturn);
    }
    if let Some(arity) = return_ty.tuple_arity()
        && arity >= 2
    {
        return Some(GoCallStrategy::Tuple { arity });
    }
    None
}

pub(crate) fn sentinel_hint(hints: &[String]) -> Option<i64> {
    hints
        .iter()
        .any(|h| h == "sentinel_minus_one")
        .then_some(-1)
}

pub(crate) fn is_nullable_option(definitions: &HashMap<Symbol, Definition>, ty: &Type) -> bool {
    ty.is_option() && is_nilable_go_type(definitions, &ty.ok_type())
}

pub(crate) fn is_nilable_go_type(definitions: &HashMap<Symbol, Definition>, ty: &Type) -> bool {
    ty.is_ref()
        || as_interface(definitions, ty).is_some()
        || resolve_to_function_type(definitions, ty).is_some()
}

pub(crate) fn as_interface(definitions: &HashMap<Symbol, Definition>, ty: &Type) -> Option<String> {
    let Type::Nominal { id, .. } = peel_alias(definitions, ty) else {
        return None;
    };
    matches!(
        definitions.get(id.as_str()).map(|d| &d.body),
        Some(DefinitionBody::Interface { .. })
    )
    .then(|| id.to_string())
}

pub(crate) fn resolve_to_function_type(
    definitions: &HashMap<Symbol, Definition>,
    ty: &Type,
) -> Option<Type> {
    fn as_function(ty: &Type) -> Option<Type> {
        if matches!(ty, Type::Function { .. }) {
            return Some(ty.clone());
        }
        ty.get_underlying()
            .filter(|u| matches!(u, Type::Function { .. }))
            .cloned()
    }
    as_function(ty).or_else(|| as_function(&peel_alias(definitions, ty)))
}

pub(crate) fn peel_alias(definitions: &HashMap<Symbol, Definition>, ty: &Type) -> Type {
    syntax::types::peel_alias(ty, |id| {
        definitions.get(id).is_some_and(Definition::is_type_alias)
    })
}

pub struct TestEmitConfig<'a> {
    pub definitions: &'a HashMap<Symbol, Definition>,
    pub module_id: &'a str,
    pub go_module: &'a str,
    pub unused: &'a UnusedInfo,
    pub mutations: &'a MutationInfo,
    pub ufcs_methods: &'a HashSet<(String, String)>,
    pub go_package_names: &'a HashMap<String, String>,
}

struct EmitContext<'a> {
    definitions: &'a HashMap<Symbol, Definition>,
    unused: &'a UnusedInfo,
    mutations: &'a MutationInfo,
    ufcs_methods: &'a HashSet<(String, String)>,
    go_package_names: &'a HashMap<String, String>,
    entry_module: ModuleId,
    go_module: String,
    options: EmitOptions,
    /// file_id -> byte offset to line lookup.
    line_indexes: Arc<HashMap<u32, LineIndex>>,
}

struct ModuleData {
    enum_layouts: HashMap<String, EnumLayout>,
    /// Fields that were exported due to serialization tags (e.g. `#[json]`).
    /// Key is "TypeId.field_name". Checked during field access to match
    /// the capitalization used in the struct definition.
    tag_exported_fields: HashSet<String>,
    /// Local complement to `GlobalEmitData::exported_method_names`.
    exported_method_names: HashSet<String>,
    /// Bounds from constrained impl blocks, keyed by receiver name.
    /// Go requires type parameter constraints on the type definition itself,
    /// so we pre-scan impl blocks and merge their bounds into struct generics.
    impl_bounds: HashMap<String, Vec<Generic>>,
    /// Types that have unconstrained impl blocks (impl<T> Type<T> with no bounds).
    /// Used to detect when a type has both constrained and unconstrained impl blocks.
    unconstrained_impl_receivers: HashSet<String>,
    /// Maps module IDs to their import aliases (e.g., "lib" → "L", "models/user" → "user").
    /// Used when emitting cross-module references to use the correct alias.
    module_aliases: HashMap<String, String>,
    /// Reverse of `module_aliases`: maps alias → module_id (e.g., "L" → "lib").
    /// Used for O(1) lookup when resolving an alias back to a module name.
    reverse_module_aliases: HashMap<String, String>,
    /// Generic type parameters whose Ref has been absorbed into the Go type parameter.
    /// When a function has `item: Ref<T>` where T has interface bounds, Go requires
    /// T itself (not *T) to satisfy the interface. So we emit `item T` and let Go
    /// infer T = *ConcreteType. Ref<T> for these params should emit as just T.
    absorbed_ref_generics: HashSet<String>,
    /// Lisette name → freshened Go name when `escape_reserved` would collide
    /// with a sibling top-level definition (e.g. `fn len` and `fn len_` both
    /// targeting `len_`). Consulted at definition and call sites.
    escape_remap: HashMap<String, String>,
}

struct ScopeState {
    next_var: usize,
    bindings: Bindings,
    /// Stack of Go variable names declared at each scope level.
    declared: Vec<HashSet<String>>,
    /// Current Go block scope depth (0 = function level).
    scope_depth: usize,
    /// Stack of loop contexts (result var + optional label) per nesting level.
    loop_stack: Vec<LoopContext>,
    /// Go variable names currently used as block-to-var assign targets.
    assign_targets: HashSet<String>,
    /// Go identifiers emitted as `const` (not `var`).
    go_const_bindings: HashSet<String>,
}

impl ScopeState {
    fn reset_for_top_level(&mut self) {
        self.next_var = 0;
        self.bindings.reset();
        self.declared.clear();
        self.declared.push(HashSet::default());
    }
}

pub struct Emitter<'a> {
    ctx: EmitContext<'a>,
    globals: Arc<GlobalEmitData>,
    module: ModuleData,
    scope: ScopeState,

    current_module: ModuleId,

    synthesized_adapter_types: HashMap<(EcoString, EcoString), String>,
    pending_adapter_types: Vec<String>,

    // Per-file accumulated state (reset between files)
    flags: EmitFlags,
    ensure_imported: HashSet<ModuleId>,

    // Temporary emission context (saved/restored per-expression).
    // These are implicit arguments — ideally parameters, but
    // plumbing through deep call chains is impractical.
    position: Position,
    current_return_context: Option<ReturnContext>,
    /// Target type for Option/Result assignment (interface coercion).
    assign_target_ty: Option<Type>,
    /// Generic function identifiers should NOT add type args when used as callees
    /// (the call site handles instantiation), only when used as values.
    emitting_call_callee: bool,
    /// Set while emitting expressions that will appear in Go `if`/`for`/`switch`
    /// conditions. Generic composite literals (`Type[Args]{...}`) need inner parens
    /// in these contexts because gofmt strips outer condition parens for generics.
    in_condition: bool,
    /// When true, `emit_regular_call` skips array return wrapping (`arr := call; arr[:]`)
    /// and returns the raw call string. Set by `emit_go_call_discarded` for discarded calls
    /// where the array-to-slice conversion is unnecessary.
    skip_array_return_wrap: bool,
    /// Declared slot type during tuple staging; recovers Go alias type args that
    /// call-site inference loses in assign-position match arms.
    current_slot_expected_ty: Option<Type>,
    /// Set when the destination is a Go-side function (e.g. a generic
    /// `func(T) U` callback) that needs the unlowered single-return form.
    suppress_go_fn_short_circuit: bool,
    /// True while emitting an argument into an `Unknown` (`any`) param;
    /// makes `emit_lambda` render `Never`-returning lambdas as `func()`
    /// (not `func() struct{}`).
    arg_flows_to_unknown: bool,
}

/// `force_tagged` is set inside try-block IIFEs whose outer signature is
/// the unwrapped `Result`; their body must return the tagged form even
/// when `ty` would normally lower.
#[derive(Clone)]
pub(crate) struct ReturnContext {
    pub(crate) ty: Type,
    pub(crate) force_tagged: bool,
}

impl ReturnContext {
    pub(crate) fn new(ty: Type) -> Self {
        Self {
            ty,
            force_tagged: false,
        }
    }

    pub(crate) fn tagged(ty: Type) -> Self {
        Self {
            ty,
            force_tagged: true,
        }
    }
}

impl<'a> Emitter<'a> {
    pub fn emit(analysis: &'a EmitInput, go_module: &str, options: EmitOptions) -> Vec<OutputFile> {
        let line_indexes: Arc<HashMap<u32, LineIndex>> = Arc::new(if options.debug {
            analysis
                .files
                .iter()
                .map(|(file_id, file)| {
                    let path = if file.module_id == analysis.entry_module_id {
                        format!("src/{}", file.name)
                    } else {
                        format!("{}/{}", file.module_id, file.name)
                    };
                    (*file_id, LineIndex::from_source(path, &file.source))
                })
                .collect()
        } else {
            HashMap::default()
        });

        let globals = Arc::new(GlobalEmitData::compute(&analysis.definitions));

        let mut work: Vec<(&ModuleId, &syntax::program::ModuleInfo)> = analysis
            .modules
            .iter()
            .filter(|(id, _)| !analysis.cached_modules.contains(*id))
            .collect();
        work.sort_unstable_by(|a, b| a.0.cmp(b.0));

        const PARALLEL_THRESHOLD: usize = 4;

        let emit_one = |&(module_id, module_info): &(&ModuleId, &syntax::program::ModuleInfo)| {
            emit_module(
                analysis,
                go_module,
                &options,
                &line_indexes,
                &globals,
                module_id,
                module_info,
            )
        };

        let mut output: Vec<OutputFile> = if work.len() < PARALLEL_THRESHOLD {
            work.iter().flat_map(emit_one).collect()
        } else {
            use rayon::prelude::*;
            work.par_iter().flat_map_iter(emit_one).collect()
        };

        output.sort_by(|a, b| a.name.cmp(&b.name));
        output
    }

    pub fn new_for_tests(config: &TestEmitConfig<'a>, source: Option<&str>) -> Self {
        let (debug, line_indexes) = match source {
            Some(src) => (
                true,
                Arc::new(HashMap::from_iter([(
                    0u32,
                    LineIndex::from_source("src/test.lis".to_string(), src),
                )])),
            ),
            None => (false, Arc::new(HashMap::default())),
        };
        let ctx = EmitContext {
            definitions: config.definitions,
            unused: config.unused,
            mutations: config.mutations,
            ufcs_methods: config.ufcs_methods,
            go_package_names: config.go_package_names,
            entry_module: config.module_id.to_string(),
            go_module: config.go_module.to_string(),
            options: EmitOptions { debug },
            line_indexes,
        };
        let globals = Arc::new(GlobalEmitData::compute(config.definitions));
        Self::new(ctx, globals, config.module_id)
    }

    fn new(ctx: EmitContext<'a>, globals: Arc<GlobalEmitData>, current_module: &str) -> Self {
        Self {
            ctx,
            globals,
            module: ModuleData {
                enum_layouts: HashMap::default(),
                tag_exported_fields: HashSet::default(),
                exported_method_names: HashSet::default(),
                impl_bounds: HashMap::default(),
                unconstrained_impl_receivers: HashSet::default(),
                module_aliases: HashMap::default(),
                reverse_module_aliases: HashMap::default(),
                absorbed_ref_generics: HashSet::default(),
                escape_remap: HashMap::default(),
            },
            scope: ScopeState {
                next_var: 0,
                bindings: Bindings::new(),
                declared: vec![HashSet::default()],
                scope_depth: 0,
                loop_stack: Vec::new(),
                assign_targets: HashSet::default(),
                go_const_bindings: HashSet::default(),
            },
            current_module: current_module.to_string(),
            synthesized_adapter_types: HashMap::default(),
            pending_adapter_types: Vec::new(),
            flags: EmitFlags::default(),
            ensure_imported: HashSet::default(),
            position: Position::Expression,
            current_return_context: None,
            assign_target_ty: None,
            emitting_call_callee: false,
            in_condition: false,
            skip_array_return_wrap: false,
            current_slot_expected_ty: None,
            suppress_go_fn_short_circuit: false,
            arg_flows_to_unknown: false,
        }
    }

    pub(crate) fn emit_condition_operand(
        &mut self,
        output: &mut String,
        expression: &syntax::ast::Expression,
    ) -> String {
        let prev = self.in_condition;
        self.in_condition = true;
        let result = self.emit_operand(output, expression);
        self.in_condition = prev;
        result
    }

    pub(crate) fn push_loop(&mut self, result_var: impl Into<String>) {
        self.scope.loop_stack.push(LoopContext {
            result_var: result_var.into(),
            label: None,
        });
    }

    pub(crate) fn pop_loop(&mut self) {
        self.scope.loop_stack.pop();
    }

    pub(crate) fn current_loop_result_var(&self) -> Option<&str> {
        self.scope
            .loop_stack
            .last()
            .map(|ctx| ctx.result_var.as_str())
    }

    pub(crate) fn current_loop_label(&self) -> Option<&str> {
        self.scope
            .loop_stack
            .last()
            .and_then(|ctx| ctx.label.as_deref())
    }

    pub(crate) fn with_position<F, R>(&mut self, position: Position, f: F) -> R
    where
        F: FnOnce(&mut Self) -> R,
    {
        let saved = std::mem::replace(&mut self.position, position);
        let result = f(self);
        self.position = saved;
        result
    }

    pub(crate) fn wrap_value(&self, value: &str) -> String {
        if value.is_empty() {
            return String::new();
        }
        match &self.position {
            Position::Tail => format!("return {}\n", value),
            Position::Statement => format!("{}\n", value),
            Position::Expression => value.to_string(),
            Position::Assign(var) => format!("{} = {}\n", var, value),
        }
    }

    pub(crate) fn emit_unreachable_if_needed(&self, output: &mut String, has_catchall: bool) {
        if self.position.is_tail() && !has_catchall {
            output.push_str("panic(\"unreachable\")\n");
        }
    }

    /// Computes the position for match arms based on the current position and result type.
    ///
    /// For control flow constructs that need to produce values (match, if-else), this
    /// determines whether we need a temporary result variable and what position the
    /// inner branches should use.
    ///
    /// If `output` is provided, declares the result variable when needed.
    pub(crate) fn compute_arm_position(
        &mut self,
        output: Option<&mut String>,
        ty: &Type,
    ) -> ArmPosition {
        if self.position.is_tail() {
            return ArmPosition::from_position(Position::Tail);
        }

        if let Some(var) = self.position.assign_target() {
            return ArmPosition::from_position(Position::Assign(var.to_string()));
        }

        if self.position.is_expression() && !ty.is_unit() {
            let var = self.fresh_var(Some("result"));
            if let Some(out) = output {
                let go_ty = self.go_type_as_string(ty);
                write_line!(out, "var {} {}", var, go_ty);
            }
            return ArmPosition::with_result_var(var);
        }

        ArmPosition::from_position(Position::Statement)
    }

    /// Checks if a Go variable name has been declared in the current scope.
    /// Tracks declarations at each scope level so variable shadowing works correctly.
    /// Returns true if this is a new declaration (use :=), false if already declared (use =).
    pub(crate) fn try_declare(&mut self, go_name: &str) -> bool {
        if let Some(current_scope) = self.scope.declared.last_mut() {
            if current_scope.contains(go_name) {
                false
            } else {
                current_scope.insert(go_name.to_string());
                true
            }
        } else {
            true
        }
    }

    pub(crate) fn is_declared(&self, go_name: &str) -> bool {
        self.scope
            .declared
            .iter()
            .any(|scope| scope.contains(go_name))
    }

    /// Unconditionally marks a Go variable name as declared in the current scope.
    /// Use this for parameters, which are always "declared" at function entry.
    pub(crate) fn declare(&mut self, go_name: &str) {
        if let Some(current_scope) = self.scope.declared.last_mut() {
            current_scope.insert(go_name.to_string());
        }
    }

    pub(crate) fn enter_scope(&mut self) {
        self.scope.scope_depth += 1;
        self.scope.bindings.save();
        self.scope.declared.push(HashSet::default());
    }

    pub(crate) fn exit_scope(&mut self) {
        self.scope.scope_depth = self.scope.scope_depth.saturating_sub(1);
        self.scope.bindings.restore();
        if self.scope.declared.len() > 1 {
            self.scope.declared.pop();
        }
    }

    pub(crate) fn current_module(&self) -> &str {
        &self.current_module
    }

    pub(crate) fn module_alias_for_type(&self, ty: &Type) -> Option<String> {
        if let Type::Nominal { id, .. } = ty {
            let module = names::go_name::module_of_type_id(id);
            self.module.module_aliases.get(module).cloned()
        } else {
            None
        }
    }

    pub(crate) fn maybe_line_directive(&self, span: &Span) -> String {
        if !self.ctx.options.debug || span.is_dummy() {
            return String::new();
        }

        let Some(source) = self.ctx.line_indexes.get(&span.file_id) else {
            return String::new();
        };

        let line = source.line_for_offset(span.byte_offset);
        let col = source.col_for_offset(span.byte_offset);

        format!("//line {}:{}:{}\n", source.path, line, col)
    }

    fn unused_imports_for_current_module<'u>(
        unused: &'u UnusedInfo,
        current_module: &str,
    ) -> &'u HashSet<EcoString> {
        static EMPTY: std::sync::LazyLock<HashSet<EcoString>> =
            std::sync::LazyLock::new(HashSet::default);
        unused
            .imports_by_module
            .get(current_module)
            .unwrap_or(&EMPTY)
    }

    pub fn emit_files(&mut self, files: &[&File], module_id: &str) -> Vec<OutputFile> {
        self.current_module = module_id.to_string();
        self.collect_module_aliases(files);
        self.collect_local_exported_method_names(files);
        self.collect_impl_bounds(files);
        self.collect_enum_layouts();
        self.collect_escape_remap(files);
        let mut make_functions_by_file = self.collect_local_make_function_code();

        let mut output_files = Vec::new();

        let package_name = if module_id == self.ctx.entry_module {
            "main".to_string()
        } else {
            let raw = module_id.rsplit('/').next().unwrap_or(module_id);
            go_name::sanitize_package_name(raw).into_owned()
        };

        for file in files {
            let mut source = OutputCollector::new();

            if let Some(functions) = make_functions_by_file.remove(&file.id) {
                for function in functions {
                    source.collect_with_blank(function);
                }
            }

            self.pending_adapter_types.clear();

            for expression in &file.items {
                self.scope.reset_for_top_level();
                let code = self.emit_top_item(expression);
                if !code.is_empty() {
                    source.collect_with_blank(code);
                }
            }

            for adapter_decl in std::mem::take(&mut self.pending_adapter_types) {
                source.collect_with_blank(adapter_decl);
            }

            let unused_imports =
                Self::unused_imports_for_current_module(self.ctx.unused, &self.current_module);
            let mut import_builder = ImportBuilder::new(
                &self.ctx.go_module,
                unused_imports,
                self.ctx.go_package_names,
            );
            import_builder.collect_from_file(file);

            let ensure_imported = std::mem::take(&mut self.ensure_imported);
            import_builder.extend_with_modules(&ensure_imported);

            let flags = std::mem::take(&mut self.flags);
            if flags.needs_fmt {
                import_builder.require_fmt();
            }
            if flags.needs_stdlib {
                import_builder.require_stdlib();
            }
            if flags.needs_errors {
                import_builder.require_errors();
            }
            if flags.needs_slices {
                import_builder.require_slices();
            }
            if flags.needs_strings {
                import_builder.require_strings();
            }
            if flags.needs_maps {
                import_builder.require_maps();
            }

            let rendered_source = source.render();
            import_builder.filter_unreferenced(&rendered_source);

            let (imports, diagnostics) = import_builder.build();
            output_files.push(OutputFile {
                name: file.go_filename(),
                imports,
                source: rendered_source,
                package_name: package_name.clone(),
                diagnostics,
            });
        }

        output_files
    }
}

fn emit_module(
    analysis: &EmitInput,
    go_module: &str,
    options: &EmitOptions,
    line_indexes: &Arc<HashMap<u32, LineIndex>>,
    globals: &Arc<GlobalEmitData>,
    module_id: &str,
    module_info: &syntax::program::ModuleInfo,
) -> Vec<OutputFile> {
    let ctx = EmitContext {
        definitions: &analysis.definitions,
        unused: &analysis.unused,
        mutations: &analysis.mutations,
        ufcs_methods: &analysis.ufcs_methods,
        go_package_names: &analysis.go_package_names,
        entry_module: analysis.entry_module_id.to_string(),
        go_module: go_module.to_string(),
        options: options.clone(),
        line_indexes: line_indexes.clone(),
    };
    let mut emitter = Emitter::new(ctx, globals.clone(), module_id);

    let files: Vec<_> = module_info
        .file_ids
        .iter()
        .filter_map(|fid| analysis.files.get(fid))
        .collect();

    let mut module_output = emitter.emit_files(&files, module_id);

    if module_id != analysis.entry_module_id.as_str() {
        for file in &mut module_output {
            file.name = format!("{}/{}", module_info.path, file.name);
        }
    }

    module_output
}