Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Support emitting direct imports in wasm files #1689

Merged
merged 1 commit into from
Aug 1, 2019
Merged

Support emitting direct imports in wasm files #1689

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
134 changes: 111 additions & 23 deletions crates/cli-support/src/js/mod.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@ use crate::webidl::{AuxValue, Binding};
use crate::webidl::{JsImport, JsImportName, NonstandardWebidlSection, WasmBindgenAux};
use crate::{Bindgen, EncodeInto, OutputMode};
use failure::{bail, Error, ResultExt};
use std::collections::{BTreeMap, HashMap, HashSet};
use std::collections::{BTreeMap, BTreeSet, HashMap, HashSet};
use std::fs;
use std::path::{Path, PathBuf};
use walrus::{ExportId, ImportId, MemoryId, Module};
Expand Down Expand Up @@ -248,7 +248,7 @@ impl<'a> Context<'a> {
OutputMode::NoModules { global } => {
js.push_str("const __exports = {};\n");
js.push_str("let wasm;\n");
init = self.gen_init(needs_manual_start);
init = self.gen_init(needs_manual_start, None)?;
footer.push_str(&format!(
"self.{} = Object.assign(init, __exports);\n",
global
Expand Down Expand Up @@ -309,7 +309,7 @@ impl<'a> Context<'a> {
// as the default export of the module.
OutputMode::Web => {
self.imports_post.push_str("let wasm;\n");
init = self.gen_init(needs_manual_start);
init = self.gen_init(needs_manual_start, Some(&mut imports))?;
footer.push_str("export default init;\n");
}
}
Expand Down Expand Up @@ -435,7 +435,11 @@ impl<'a> Context<'a> {
)
}

fn gen_init(&mut self, needs_manual_start: bool) -> (String, String) {
fn gen_init(
&mut self,
needs_manual_start: bool,
mut imports: Option<&mut String>,
) -> Result<(String, String), Error> {
let module_name = "wbg";
let mem = self.module.memories.get(self.memory);
let (init_memory1, init_memory2) = if let Some(id) = mem.import {
Expand Down Expand Up @@ -495,6 +499,30 @@ impl<'a> Context<'a> {
imports_init.push_str(";\n");
}

let extra_modules = self
.module
.imports
.iter()
.filter(|i| !self.wasm_import_definitions.contains_key(&i.id()))
.filter(|i| {
// Importing memory is handled specially in this area, so don't
// consider this a candidate for importing from extra modules.
match i.kind {
walrus::ImportKind::Memory(_) => false,
_ => true,
}
})
.map(|i| &i.module)
.collect::<BTreeSet<_>>();
for (i, extra) in extra_modules.iter().enumerate() {
let imports = match &mut imports {
Some(list) => list,
None => bail!("cannot import from modules (`{}`) with `--no-modules`", extra),
};
imports.push_str(&format!("import * as __wbg_star{} from '{}';\n", i, extra));
imports_init.push_str(&format!("imports['{}'] = __wbg_star{};\n", extra, i));
}

let js = format!(
"\
function init(module{init_memory_arg}) {{
Expand Down Expand Up @@ -553,7 +581,7 @@ impl<'a> Context<'a> {
imports_init = imports_init,
);

(js, ts)
Ok((js, ts))
}

fn write_classes(&mut self) -> Result<(), Error> {
Expand Down Expand Up @@ -1104,15 +1132,17 @@ impl<'a> Context<'a> {
//
// If `ptr` and `len` are both `0` then that means it's `None`, in that case we rely upon
// the fact that `getObject(0)` is guaranteed to be `undefined`.
self.global("
self.global(
"
function getCachedStringFromWasm(ptr, len) {
if (ptr === 0) {
return getObject(len);
} else {
return getStringFromWasm(ptr, len);
}
}
");
",
);
Ok(())
}

Expand Down Expand Up @@ -1730,7 +1760,8 @@ impl<'a> Context<'a> {

JsImportName::LocalModule { module, name } => {
let unique_name = generate_identifier(name, &mut self.defined_identifiers);
add_module_import(format!("./snippets/{}", module), name, &unique_name);
let module = self.config.local_module_name(module);
add_module_import(module, name, &unique_name);
unique_name
}

Expand All @@ -1739,11 +1770,10 @@ impl<'a> Context<'a> {
snippet_idx_in_crate,
name,
} => {
let module = self
.config
.inline_js_module_name(unique_crate_identifier, *snippet_idx_in_crate);
let unique_name = generate_identifier(name, &mut self.defined_identifiers);
let module = format!(
"./snippets/{}/inline{}.js",
unique_crate_identifier, snippet_idx_in_crate,
);
add_module_import(module, name, &unique_name);
unique_name
}
Expand Down Expand Up @@ -2014,16 +2044,11 @@ impl<'a> Context<'a> {
.types
.get::<ast::WebidlFunction>(binding.webidl_ty)
.unwrap();
let js = match import {
match import {
AuxImport::Value(AuxValue::Bare(js))
if !variadic && !catch && self.import_does_not_require_glue(binding, webidl) =>
{
self.expose_not_defined();
let name = self.import_name(js)?;
format!(
"typeof {name} == 'function' ? {name} : notDefined('{name}')",
name = name,
)
self.direct_import(id, js)
}
_ => {
if assert_no_shim {
Expand All @@ -2048,11 +2073,11 @@ impl<'a> Context<'a> {
cx.invoke_import(&binding, import, bindings, args, variadic, prelude)
},
)?;
format!("function{}", js)
self.wasm_import_definitions
.insert(id, format!("function{}", js));
Ok(())
}
};
self.wasm_import_definitions.insert(id, js);
Ok(())
}
}

fn import_does_not_require_glue(
Expand All @@ -2078,6 +2103,69 @@ impl<'a> Context<'a> {
)
}

/// Emit a direct import directive that hooks up the `js` value specified to
/// the wasm import `id`.
fn direct_import(&mut self, id: ImportId, js: &JsImport) -> Result<(), Error> {
// If there's no field projection happening here and this is a direct
// import from an ES-looking module, then we can actually just hook this
// up directly in the wasm file itself. Note that this is covered in the
// various output formats as well:
//
// * `bundler` - they think wasm is an ES module anyway
// * `web` - we're sure to emit more `import` directives during
// `gen_init` and we update the import object accordingly.
// * `nodejs` - the polyfill we have for requiring a wasm file as a node
// module will naturally emit `require` directives for the module
// listed on each wasm import.
// * `no-modules` - imports aren't allowed here anyway from other
// modules and an error is generated.
if js.fields.len() == 0 {
match &js.name {
JsImportName::Module { module, name } => {
let import = self.module.imports.get_mut(id);
import.module = module.clone();
import.name = name.clone();
return Ok(());
}
JsImportName::LocalModule { module, name } => {
let module = self.config.local_module_name(module);
let import = self.module.imports.get_mut(id);
import.module = module;
import.name = name.clone();
return Ok(());
}
JsImportName::InlineJs {
unique_crate_identifier,
snippet_idx_in_crate,
name,
} => {
let module = self
.config
.inline_js_module_name(unique_crate_identifier, *snippet_idx_in_crate);
let import = self.module.imports.get_mut(id);
import.module = module;
import.name = name.clone();
return Ok(());
}

// Fall through below to requiring a JS shim to create an item
// that we can import. These are plucked from the global
// environment so there's no way right now to describe these
// imports in an ES module-like fashion.
JsImportName::Global { .. } | JsImportName::VendorPrefixed { .. } => {}
}
}

self.expose_not_defined();
let name = self.import_name(js)?;
let js = format!(
"typeof {name} == 'function' ? {name} : notDefined('{name}')",
name = name,
);
self.wasm_import_definitions.insert(id, js);
Ok(())
}

/// Generates a JS snippet appropriate for invoking `import`.
///
/// This is generating code for `binding` where `bindings` has more type
Expand Down
15 changes: 15 additions & 0 deletions crates/cli-support/src/lib.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -360,6 +360,21 @@ impl Bindgen {
typescript: self.typescript,
})
}

fn local_module_name(&self, module: &str) -> String {
format!("./snippets/{}", module)
}

fn inline_js_module_name(
&self,
unique_crate_identifier: &str,
snippet_idx_in_crate: usize,
) -> String {
format!(
"./snippets/{}/inline{}.js",
unique_crate_identifier, snippet_idx_in_crate,
)
}
}

fn reset_indentation(s: &str) -> String {
Expand Down