Test Iroh path selection without sleeps

.github/actions/setup-cmux-tui-rust/action.yml

@@ -0,0 +1,57 @@
+name: Set up cmux-tui Rust
+description: Install the repository-pinned cmux-tui Rust toolchain.
+
+runs:
+  using: composite
+  steps:
+    - name: Install pinned Rust toolchain
+      shell: bash
+      env:
+        TOOLCHAIN_FILE: ${{ github.action_path }}/../../../cmux-tui/rust-toolchain.toml
+      run: |
+        if command -v python3 >/dev/null 2>&1; then
+          python_cmd=python3
+        elif command -v python >/dev/null 2>&1; then
+          python_cmd=python
+        else
+          echo "::error::Python is required to read the pinned Rust toolchain" >&2
+          exit 1
+        fi
+        "$python_cmd" <<'PY'
+        import os
+        import pathlib
+        import re
+        import subprocess
+
+        contents = pathlib.Path(os.environ["TOOLCHAIN_FILE"]).read_text(encoding="utf-8")
+
+        def value(name):
+            match = re.search(rf'^\s*{name}\s*=\s*"([^"]+)"', contents, re.MULTILINE)
+            if match is None:
+                raise SystemExit(f"missing {name} in cmux-tui/rust-toolchain.toml")
+            return match.group(1)
+
+        channel = value("channel")
+        profile = value("profile")
+        components_match = re.search(r"^\s*components\s*=\s*\[([^]]*)\]", contents, re.MULTILINE)
+        if components_match is None:
+            raise SystemExit("missing components in cmux-tui/rust-toolchain.toml")
+        components = re.findall(r'"([^"]+)"', components_match.group(1))
+
+        command = ["rustup", "toolchain", "install", channel, "--profile", profile]
+        for component in components:
+            command.extend(["--component", component])
+        subprocess.run(command, check=True)
+        subprocess.run(["rustup", "default", channel], check=True)
+
+        cargo = subprocess.run(
+            ["rustup", "which", "cargo"],
+            check=True,
+            capture_output=True,
+            text=True,
+        ).stdout.strip()
+        with open(os.environ["GITHUB_PATH"], "a", encoding="utf-8") as path_file:
+            print(pathlib.Path(cargo).parent, file=path_file)
+        PY
+        cargo --version
+        rustc --version

.github/scripts/run-cmux-tui-core-tests-isolated.py

@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+"""Run each cmux-tui-core Rust test in a fresh process."""
+
+from __future__ import annotations
+
+import argparse
+import json
+from pathlib import Path
+import subprocess
+import sys
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("cargo_messages", type=Path)
+    parser.add_argument("core_root", type=Path)
+    return parser.parse_args()
+
+
+def is_below(path: Path, root: Path) -> bool:
+    try:
+        path.relative_to(root)
+    except ValueError:
+        return False
+    return True
+
+
+def test_binaries(cargo_messages: Path, core_root: Path) -> list[Path]:
+    binaries: dict[Path, set[str]] = {}
+    with cargo_messages.open(encoding="utf-8") as messages:
+        for line in messages:
+            try:
+                message = json.loads(line)
+            except json.JSONDecodeError:
+                continue
+            if message.get("reason") != "compiler-artifact":
+                continue
+            if not message.get("profile", {}).get("test"):
+                continue
+
+            target = message.get("target", {})
+            kinds = set(target.get("kind", []))
+            if not kinds.intersection({"lib", "test"}):
+                continue
+            source = target.get("src_path")
+            executable = message.get("executable")
+            if not source or not executable:
+                continue
+            if not is_below(Path(source).resolve(), core_root):
+                continue
+            binaries.setdefault(Path(executable).resolve(), set()).update(kinds)
+
+    library_binaries = [path for path, kinds in binaries.items() if "lib" in kinds]
+    if len(library_binaries) != 1:
+        raise SystemExit(
+            "expected one cmux-tui-core library test binary, "
+            f"found {len(library_binaries)}"
+        )
+    if not binaries:
+        raise SystemExit("cargo did not report any cmux-tui-core test binaries")
+    return sorted(binaries)
+
+
+def tests_in(binary: Path) -> list[str]:
+    result = subprocess.run(
+        [str(binary), "--list"],
+        check=True,
+        stdout=subprocess.PIPE,
+        text=True,
+    )
+    tests = []
+    for line in result.stdout.splitlines():
+        name, separator, kind = line.rpartition(": ")
+        if separator and kind == "test":
+            tests.append(name)
+    if not tests:
+        raise SystemExit(f"{binary.name} did not list any tests")
+    if len(tests) != len(set(tests)):
+        raise SystemExit(f"{binary.name} listed duplicate test names")
+    return tests
+
+
+def main() -> int:
+    args = parse_args()
+    core_root = args.core_root.resolve()
+    binaries = test_binaries(args.cargo_messages, core_root)
+    total = 0
+    for binary in binaries:
+        tests = tests_in(binary)
+        print(f"Running {len(tests)} tests from {binary.name} in fresh processes")
+        for index, test_name in enumerate(tests, start=1):
+            print(f"[{index}/{len(tests)}] {test_name}", flush=True)
+            subprocess.run(
+                [str(binary), test_name, "--exact", "--test-threads=1"],
+                check=True,
+            )
+            total += 1
+    print(f"Passed {total} isolated cmux-tui-core tests")
+    return 0
+
+
+if __name__ == "__main__":
+    sys.exit(main())