Add code coverage check (#13)

* add code coverage check

* mdformat

Author: matth2k

.github/workflows/rust.yml

@@ -41,3 +41,42 @@ jobs:
       - uses: actions/checkout@v4
       - name: Run Clippy
         run: cargo clippy --all-targets --features default
+
+  coverage:
+    name: Code Coverage
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions-rust-lang/setup-rust-toolchain@v1
+      - name: Install cargo-llvm-cov
+        uses: taiki-e/install-action@cargo-llvm-cov
+      - name: Generate code coverage
+        run: cargo llvm-cov --features default --workspace --json > coverage.json
+      - name: Coverage (60% by line)
+        run: python3 utils/code_coverage.py -p 60.0 coverage.json >> $GITHUB_STEP_SUMMARY
+      - name: Coverage (80% by line)
+        run: python3 utils/code_coverage.py -p 80.0 coverage.json >> $GITHUB_STEP_SUMMARY
+      - name: Coverage (90% by line)
+        run: python3 utils/code_coverage.py -p 90.0 coverage.json >> $GITHUB_STEP_SUMMARY
+
+  mdformat:
+    name: Markdown format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Markdown check format
+        uses: ydah/mdformat-action@main
+        with:
+          number: true
+
+
+  pyformat:
+    name: Python format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Format python code
+        uses: psf/black@stable
+        with:
+          options: "--check --verbose"
+          src: "./utils"

Cargo.toml

@@ -2,7 +2,7 @@
 name = "circuit"
 version = "0.1.0"
 edition = "2024"
-default-run = "main"
+license = "MIT OR Apache-2.0"
 
 [dependencies]
 bitvec = { version = "1.0.1" }

README.md

@@ -58,4 +58,3 @@ However, you may want to use another library that leverages a denser representat
 Then, open it up and take a look:
 
 ![Ripple-carry adder](doc/adder.svg)
-

utils/code_coverage.py

@@ -0,0 +1,114 @@
+# Copyright 2025 The Circuit Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import argparse
+import sys
+import os
+import json
+
+# cargo llvm-cov --all-features --workspace --json
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "-p",
+        "--percent",
+        dest="percent",
+        required=False,
+        help="Minimum code coverage per line per source file",
+        type=float,
+        default=80.0,
+    )
+    parser.add_argument(
+        "-w",
+        "--whitelist",
+        dest="whitelist",
+        nargs="+",
+        help="Files to whitelist from coverage checks",
+        type=str,
+        default=["main.rs"],
+    )
+    parser.add_argument(
+        "input", nargs="?", type=argparse.FileType("r"), default=sys.stdin
+    )
+    parser.add_argument(
+        "output", nargs="?", type=argparse.FileType("w"), default=sys.stdout
+    )
+    args = parser.parse_args()
+
+    whitelisted = set(args.whitelist)
+    data = json.load(args.input)
+    data = data["data"]
+    percent = args.percent
+    passed = True
+
+    print(f"### Code Coverage Summary ({percent:.2f}%)", file=args.output)
+
+    for datum in data:
+        files = datum["files"]
+        for record in files:
+            filePassed = True
+            name = record["filename"]
+            stem = (
+                os.path.basename(os.path.dirname(name)) + "/" + os.path.basename(name)
+            )
+            if stem in whitelisted:
+                continue
+            lineCoverage = record["summary"]["lines"]["percent"]
+            if lineCoverage < percent:
+                print(
+                    f"#### {name}: Only {lineCoverage:.2f}% by line", file=args.output
+                )
+                print(f"```rust", file=args.output)
+                passed = False
+                with open(name, "r") as f:
+                    lines = f.readlines()
+                    covered = set()
+                    startSeg = True
+                    lastLine = None
+                    for segment in record["segments"]:
+                        line = max(segment[0] - 1, 0)
+
+                        if (
+                            lastLine is not None
+                            and line not in covered
+                            and line != lastLine + 1
+                        ):
+                            startSeg = True
+
+                        if startSeg:
+                            print(
+                                f"// {stem}:{line}",
+                                file=args.output,
+                            )
+                            startSeg = False
+
+                        executed = segment[2] != 0
+                        if not executed:
+                            txt = lines[line].strip("\n").removeprefix(" }")
+                            if (
+                                line not in covered
+                                and len(lines[line].strip(" \n").removeprefix("}")) > 0
+                            ):
+                                print(
+                                    f"{txt}",
+                                    file=args.output,
+                                )
+
+                        covered.add(line)
+                        lastLine = line
+                print(f"```", file=args.output)
+
+    if passed:
+        print("### All files passed", file=args.output)
+    sys.exit(0 if passed else 1)