Fix issue #65: Check source directories exist before writing to requirements

.gitignore

@@ -19,3 +19,4 @@ requirements-mxdev.txt
 .venv/
 dist/
 src/mxdev/_version.py
+.claude

CHANGES.md

@@ -2,6 +2,8 @@
 
 ## 5.0.1 (unreleased)
 
+- Fix #65: Check source directories exist before writing to requirements-mxdev.txt. In **offline mode**: missing sources log WARNING and are written as comments (expected behavior). In **non-offline mode**: missing sources log ERROR and mxdev exits with RuntimeError (fatal error indicating checkout failure). This fixes mxmake two-stage installation workflow and prevents silent failures when sources fail to check out.
+  [jensens]
 - Fix: Add 'synchronize' event to pull_request workflow triggers. This ensures CI runs when PRs are updated with new commits (e.g., after rebasing or pushing new changes), not just when opened or reopened.
   [jensens]
 - Chore: Optimize GitHub Actions to prevent duplicate workflow runs on pull requests. Restrict `push` trigger to only run on `main` branch, so PRs only trigger via `pull_request` event. This reduces CI resource usage by 50% for PR workflows.

src/mxdev/processing.py

@@ -210,26 +210,70 @@ def fetch(state: State) -> None:
     )
 
 
-def write_dev_sources(fio, packages: dict[str, dict[str, typing.Any]]):
+def write_dev_sources(fio, packages: dict[str, dict[str, typing.Any]], state: State):
     """Create requirements configuration for fetched source packages."""
     if not packages:
         return
+
+    # Check if we're in offline mode or no-fetch mode
+    from .config import to_bool
+
+    offline_mode = to_bool(state.configuration.settings.get("offline", False))
+    missing_sources = []  # Track missing sources for error handling
+
     fio.write("#" * 79 + "\n")
     fio.write("# mxdev development sources\n")
+
     for name, package in packages.items():
         if package["install-mode"] == "skip":
             continue
+
+        # Check if source directory exists
+        source_path = Path(package["path"])
+
         extras = f"[{package['extras']}]" if package["extras"] else ""
         subdir = f"/{package['subdirectory']}" if package["subdirectory"] else ""
 
         # Add -e prefix only for 'editable' mode (not for 'fixed')
         prefix = "-e " if package["install-mode"] == "editable" else ""
-        install_line = f"""{prefix}./{package['target']}/{name}{subdir}{extras}\n"""
+        install_line = f"""{prefix}./{package['target']}/{name}{subdir}{extras}"""
+
+        if not source_path.exists():
+            # Source not checked out yet - write as comment
+            missing_sources.append(name)
+
+            if offline_mode:
+                # In offline mode, missing sources are expected - log as WARNING
+                reason = (
+                    f"Source directory does not exist: {source_path} (package: {name}). "
+                    f"This is expected in offline mode. Run mxdev without -n and --offline flags to fetch sources."
+                )
+                logger.warning(reason)
+            else:
+                # In non-offline mode, missing sources are a fatal error - log as ERROR
+                reason = (
+                    f"Source directory does not exist: {source_path} (package: {name}). "
+                    f"This indicates a failure in the checkout process. "
+                    f"Run mxdev without -n flag to fetch sources."
+                )
+                logger.error(reason)
+
+            fio.write(f"# {install_line}  # mxdev: source not checked out\n")
+        else:
+            # Source exists - write normally
+            logger.debug(f"-> {install_line}")
+            fio.write(f"{install_line}\n")
 
-        logger.debug(f"-> {install_line.strip()}")
-        fio.write(install_line)
     fio.write("\n\n")
 
+    # In non-offline mode, missing sources are a fatal error
+    if not offline_mode and missing_sources:
+        raise RuntimeError(
+            f"Source directories missing for packages: {', '.join(missing_sources)}. "
+            f"This indicates a failure in the checkout process. "
+            f"Run mxdev without -n flag to fetch sources."
+        )
+
 
 def write_dev_overrides(fio, overrides: dict[str, str], package_keys: list[str]):
     """Create requirements configuration for overridden packages."""
@@ -292,6 +336,6 @@ def write(state: State) -> None:
             fio.write("#" * 79 + "\n")
             fio.write("# mxdev combined constraints\n")
             fio.write(f"-c {constraints_ref}\n\n")
-        write_dev_sources(fio, cfg.packages)
+        write_dev_sources(fio, cfg.packages, state)
         fio.writelines(requirements)
         write_main_package(fio, cfg.settings)