Add initial support for wasm-pack

.github/.cspell/project-dictionary.txt

@@ -14,10 +14,12 @@ nextest
 notcovered
 profdata
 profraw
+profraws
 rustfilt
 TESTNAME
 trybuild
 winapi
 xargo
 Xdemangler
 xtask
+Cinstrument

README.md

@@ -16,21 +16,23 @@ This is a wrapper around rustc [`-C instrument-coverage`][instrument-coverage] a
 
 **Table of Contents:**
 
-- [Usage](#usage)
-  - [Basic usage](#basic-usage)
-  - [Merge coverages generated under different test conditions](#merge-coverages-generated-under-different-test-conditions)
-  - [Get coverage of C/C++ code linked to Rust library/binary](#get-coverage-of-cc-code-linked-to-rust-librarybinary)
-  - [Get coverage of external tests](#get-coverage-of-external-tests)
-  - [Exclude file from coverage](#exclude-file-from-coverage)
-  - [Exclude function from coverage](#exclude-function-from-coverage)
-  - [Continuous Integration](#continuous-integration)
-  - [Display coverage in VS Code](#display-coverage-in-vs-code)
-  - [Environment variables](#environment-variables)
-  - [Additional JSON information](#additional-json-information)
-- [Installation](#installation)
-- [Known limitations](#known-limitations)
-- [Related Projects](#related-projects)
-- [License](#license)
+- [cargo-llvm-cov](#cargo-llvm-cov)
+  - [Usage](#usage)
+    - [Basic usage](#basic-usage)
+    - [Merge coverages generated under different test conditions](#merge-coverages-generated-under-different-test-conditions)
+    - [Get coverage of `wasm-pack test`](#get-coverage-of-wasm-pack-test)
+    - [Get coverage of C/C++ code linked to Rust library/binary](#get-coverage-of-cc-code-linked-to-rust-librarybinary)
+    - [Get coverage of external tests](#get-coverage-of-external-tests)
+    - [Exclude file from coverage](#exclude-file-from-coverage)
+    - [Exclude function from coverage](#exclude-function-from-coverage)
+    - [Continuous Integration](#continuous-integration)
+    - [Display coverage in VS Code](#display-coverage-in-vs-code)
+    - [Environment variables](#environment-variables)
+    - [Additional JSON information](#additional-json-information)
+  - [Installation](#installation)
+  - [Known limitations](#known-limitations)
+  - [Related Projects](#related-projects)
+  - [License](#license)
 
 ## Usage
 
@@ -420,6 +422,18 @@ cargo llvm-cov report --lcov # generate report without tests
 
 Note: To include coverage for doctests you also need to pass `--doctests` to `cargo llvm-cov report`.
 
+### Get coverage of `wasm-pack test`
+
+You can use the `wasm-pack` subcommand to run `wasm-pack test` and get coverage output from that.
+
+```sh
+cargo llvm-cov wasm-pack --chrome --headless
+```
+
+You can also merge this with normal `cargo test` [by following the instructions on merging](https://github.com/taiki-e/cargo-llvm-cov/pull/338).
+
+Note: This command is  experimental and sometimes breaks requiring a `cargo clean` to continue.
+
 ### Get coverage of C/C++ code linked to Rust library/binary
 
 Set `CC`, `CXX`, `LLVM_COV`, and `LLVM_PROFDATA` environment variables to Clang/LLVM compatible with the LLVM version used in rustc, and run cargo-llvm-cov with `--include-ffi` flag.

src/clean.rs

@@ -17,7 +17,7 @@ use crate::{
     fs,
     metadata::PackageId,
     regex_vec::{RegexVec, RegexVecBuilder},
-    term,
+    term, wasm_target_dir,
 };
 
 pub(crate) fn run(args: &mut Args) -> Result<()> {

src/cli.rs

@@ -541,7 +541,10 @@ impl Args {
             }
         }
         match subcommand {
-            Subcommand::None | Subcommand::Nextest { .. } | Subcommand::NextestArchive => {}
+            Subcommand::None
+            | Subcommand::Nextest { .. }
+            | Subcommand::NextestArchive
+            | Subcommand::WasmPack => {}
             Subcommand::Test => {
                 if no_run {
                     unexpected("--no-run", subcommand)?;
@@ -591,7 +594,8 @@ impl Args {
             | Subcommand::Test
             | Subcommand::Run
             | Subcommand::Nextest { .. }
-            | Subcommand::NextestArchive => {}
+            | Subcommand::NextestArchive
+            | Subcommand::WasmPack => {}
             _ => {
                 if !bin.is_empty() {
                     unexpected("--bin", subcommand)?;
@@ -619,6 +623,7 @@ impl Args {
             | Subcommand::Run
             | Subcommand::Nextest { .. }
             | Subcommand::NextestArchive
+            | Subcommand::WasmPack
             | Subcommand::ShowEnv => {}
             _ => {
                 if no_cfg_coverage {
@@ -634,7 +639,8 @@ impl Args {
             | Subcommand::Test
             | Subcommand::Nextest { .. }
             | Subcommand::NextestArchive
-            | Subcommand::Clean => {}
+            | Subcommand::Clean
+            | Subcommand::WasmPack => {}
             _ => {
                 if workspace {
                     unexpected("--workspace", subcommand)?;
@@ -930,6 +936,9 @@ pub(crate) enum Subcommand {
     /// Build and archive tests with cargo nextest
     NextestArchive,
 
+    /// Run tests with wasm-pack
+    WasmPack,
+
     // internal (unstable)
     Demangle,
 }
@@ -946,7 +955,10 @@ static CARGO_LLVM_COV_NEXTEST_ARCHIVE_USAGE: &str =
 
 impl Subcommand {
     fn can_passthrough(subcommand: Self) -> bool {
-        matches!(subcommand, Self::Test | Self::Run | Self::Nextest { .. } | Self::NextestArchive)
+        matches!(
+            subcommand,
+            Self::Test | Self::Run | Self::Nextest { .. } | Self::NextestArchive | Self::WasmPack
+        )
     }
 
     fn help_text(subcommand: Self) -> &'static str {
@@ -959,6 +971,7 @@ impl Subcommand {
             Self::ShowEnv => CARGO_LLVM_COV_SHOW_ENV_USAGE,
             Self::Nextest { .. } => CARGO_LLVM_COV_NEXTEST_USAGE,
             Self::NextestArchive => CARGO_LLVM_COV_NEXTEST_ARCHIVE_USAGE,
+            Self::WasmPack => todo!(),
             Self::Demangle => "", // internal API
         }
     }
@@ -973,6 +986,7 @@ impl Subcommand {
             Self::ShowEnv => "show-env",
             Self::Nextest { .. } => "nextest",
             Self::NextestArchive => "nextest-archive",
+            Self::WasmPack => "wasm-pack",
             Self::Demangle => "demangle",
         }
     }
@@ -994,6 +1008,7 @@ impl FromStr for Subcommand {
             "show-env" => Ok(Self::ShowEnv),
             "nextest" => Ok(Self::Nextest { archive_file: false }),
             "nextest-archive" => Ok(Self::NextestArchive),
+            "wasm-pack" => Ok(Self::WasmPack),
             "demangle" => Ok(Self::Demangle),
             _ => bail!("unrecognized subcommand {s}"),
         }

src/main.rs

@@ -11,7 +11,7 @@ use std::{
     collections::{BTreeSet, HashMap},
     ffi::{OsStr, OsString},
     io::{self, BufRead, Write},
-    path::Path,
+    path::{Path, PathBuf},
     time::SystemTime,
 };
 
@@ -105,6 +105,15 @@ fn try_main() -> Result<()> {
             create_dirs(cx)?;
             archive_nextest(cx)?;
         }
+        Subcommand::WasmPack => {
+            let cx = &Context::new(args)?;
+            clean::clean_partial(cx)?;
+            create_dirs(cx)?;
+            wasm_pack_test(cx)?;
+            if !cx.args.cov.no_report {
+                generate_report(cx)?;
+            }
+        }
         Subcommand::None | Subcommand::Test => {
             let cx = &Context::new(args)?;
             clean::clean_partial(cx)?;
@@ -496,6 +505,72 @@ fn run_run(cx: &Context) -> Result<()> {
     Ok(())
 }
 
+// Sanitizes the crate name so we know which .ll file to compile
+fn crate_name_to_llvm_name(crate_name: &str) -> String {
+    crate_name.replace('-', "_")
+}
+
+fn compile_ll_file(cx: &Context, prefix: &str) -> Result<()> {
+    // There are multiple ll files generated per crate, but only one wasm which has
+    // an ll file with the same file stem sitting next to it.
+    // That's the ll file we want.
+    let path = wasm_target_dir(&cx.ws);
+    let glob = glob::glob(
+        Utf8Path::new(&glob::Pattern::escape(&path.to_string()))
+            .join(format!("{prefix}-*.wasm"))
+            .as_str(),
+    )?;
+    let Some(newest) = glob
+        .filter_map(Result::ok)
+        .max_by_key(|p| std::fs::metadata(p).unwrap().created().unwrap())
+    else {
+        return Ok(());
+    };
+
+    let stem = newest.file_stem().unwrap().to_str().unwrap();
+    let src = format!("{path}/{stem}.ll");
+    let dst = format!("{path}/{stem}.o");
+
+    let mut cmd = cmd!("clang");
+    cmd.arg(src);
+    cmd.arg("-Wno-override-module");
+    cmd.arg("-c");
+    cmd.arg("-o");
+    cmd.arg(dst);
+    cmd.run()?;
+    Ok(())
+}
+
+fn compile_ll_files(cx: &Context) -> Result<()> {
+    for id in &cx.ws.metadata.workspace_members {
+        let prefix = crate_name_to_llvm_name(&cx.ws.metadata.packages[&id].name);
+        compile_ll_file(cx, &prefix)?;
+    }
+    Ok(())
+}
+
+fn wasm_profraw_prefix(ws: &Workspace) -> String {
+    format!("{}-", ws.name)
+}
+
+fn wasm_pack_test(cx: &Context) -> Result<()> {
+    let mut cmd = cmd!("wasm-pack");
+    cmd.arg("test");
+    cmd.arg("--coverage");
+    cmd.args(["--profraw-out", &cx.ws.target_dir.to_string()]);
+    cmd.args(["--profraw-prefix", &wasm_profraw_prefix(&cx.ws)]);
+    cmd.args(cx.args.cargo_args.clone());
+    cmd.args(["--target-dir", cx.ws.target_dir.as_ref()]);
+
+    // Emit llvm-ir to obtain debug info (https://github.com/hknio/code-coverage-for-webassembly)
+    cmd.env("RUSTFLAGS", "-Cinstrument-coverage -Zno-profiler-runtime --emit=llvm-ir");
+    cmd.run()?;
+
+    compile_ll_files(cx)?;
+
+    Ok(())
+}
+
 fn stdout_to_stderr(cx: &Context, cargo: &mut ProcessBuilder) {
     if cx.args.cov.no_report
         || cx.args.cov.output_dir.is_some()
@@ -509,9 +584,17 @@ fn stdout_to_stderr(cx: &Context, cargo: &mut ProcessBuilder) {
 }
 
 fn generate_report(cx: &Context) -> Result<()> {
-    merge_profraw(cx).context("failed to merge profile data")?;
+    let profraws = merge_profraw(cx).context("failed to merge profile data")?;
 
-    let object_files = object_files(cx).context("failed to collect object files")?;
+    let mut object_files = object_files(cx).context("failed to collect object files")?;
+    object_files.append(&mut wasm_object_files(&cx.ws, &profraws));
+    if object_files.is_empty() {
+        warn!(
+            "not found object files (this may occur if \
+             show-env subcommand is used incorrectly (see docs or other warnings), or unsupported \
+             commands such as nextest archive are used",
+        );
+    }
     let ignore_filename_regex = ignore_filename_regex(cx);
     let format = Format::from_args(cx);
     format
@@ -613,6 +696,10 @@ fn generate_report(cx: &Context) -> Result<()> {
     Ok(())
 }
 
+fn wasm_target_dir(ws: &Workspace) -> Utf8PathBuf {
+    format!("{}/wasm32-unknown-unknown/debug/deps", ws.target_dir).into()
+}
+
 fn open_report(cx: &Context, path: &Utf8Path) -> Result<()> {
     match &cx.ws.config.doc.browser {
         Some(browser) => {
@@ -627,7 +714,7 @@ fn open_report(cx: &Context, path: &Utf8Path) -> Result<()> {
     Ok(())
 }
 
-fn merge_profraw(cx: &Context) -> Result<()> {
+fn merge_profraw(cx: &Context) -> Result<Vec<PathBuf>> {
     // Convert raw profile data.
     let profraw_files = glob::glob(
         Utf8Path::new(&glob::Pattern::escape(cx.ws.target_dir.as_str())).join("*.profraw").as_str(),
@@ -642,7 +729,7 @@ fn merge_profraw(cx: &Context) -> Result<()> {
         );
     }
     let mut input_files = String::new();
-    for path in profraw_files {
+    for path in &profraw_files {
         input_files.push_str(
             path.to_str().with_context(|| format!("{path:?} contains invalid utf-8 data"))?,
         );
@@ -666,7 +753,7 @@ fn merge_profraw(cx: &Context) -> Result<()> {
         status!("Running", "{cmd}");
     }
     cmd.stdout_to_stderr().run()?;
-    Ok(())
+    Ok(profraw_files)
 }
 
 fn object_files(cx: &Context) -> Result<Vec<OsString>> {
@@ -807,15 +894,28 @@ fn object_files(cx: &Context) -> Result<Vec<OsString>> {
 
     // This sort is necessary to make the result of `llvm-cov show` match between macos and linux.
     files.sort_unstable();
+    Ok(files)
+}
 
-    if files.is_empty() {
-        warn!(
-            "not found object files (searched directories: {searched_dir}); this may occur if \
-             show-env subcommand is used incorrectly (see docs or other warnings), or unsupported \
-             commands such as nextest archive are used",
-        );
+fn wasm_object_files(ws: &Workspace, profraws: &[PathBuf]) -> Vec<OsString> {
+    let mut ret = Vec::new();
+    for file in profraws {
+        // The profraws on this list definitely have file names which are valid utf8
+        // otherwise they wouldn't have made it onto the list
+        let fname = file.file_name().unwrap().to_str().unwrap();
+        let prefix = format!("{}wbg-tmp-", wasm_profraw_prefix(ws));
+        let Some(stem): Option<PathBuf> = fname
+            .strip_prefix(&prefix)
+            .and_then(|s| s.strip_suffix(".wasm.profraw"))
+            .map(|s| s.into())
+        else {
+            // Didn't match prefix or suffix
+            continue;
+        };
+        let obj = wasm_target_dir(ws).join(format!("{}.o", stem.display()));
+        ret.push(obj.as_os_str().to_owned())
     }
-    Ok(files)
+    ret
 }
 
 struct Targets {

tests/test.rs

@@ -341,7 +341,8 @@ fn invalid_arg() {
                 ));
             }
         }
-        if !matches!(subcommand, "" | "test" | "run" | "nextest" | "nextest-archive") {
+        if !matches!(subcommand, "" | "test" | "run" | "nextest" | "nextest-archive" | "wasm-pack")
+        {
             for arg in [
                 "--bin=v",
                 "--example=v",