fix: git check-ignore cannot follow symlinks (#108)

```
java.lang.Exception: git check-ignore failed:
```

For exit code 1 - None of the provided paths are ignored.

```
java.lang.Exception: git check-ignore failed with code 128:
fatal: pathspec 'rust/protos/meta_event.proto' is beyond a symbolic link
```

For cannot follow symlinks.

Signed-off-by: tison <wander4096@gmail.com>

hawkeye-core/src/main/java/io/korandoru/hawkeye/core/GitHelper.java

@@ -81,24 +81,32 @@ public GitHelper(Path baseDir) {
  public void filterIgnoredFiles(Collection<String> files) {
  final Process p = new ProcessBuilder()
  .directory(baseDir.toFile())
- .command("git", "check-ignore", "--stdin", "--no-index")
+ .command("git", "check-ignore", "--stdin")
  .start();
 
- final String output;
+ final Collection<String> localFiles = files.stream()
+ .filter(file -> noSymbolLink(baseDir.resolve(file)))
+ .toList();
 
+ log.debug("git check-ignore inputs {}", localFiles);
+ final String output;
  try (OutputStream pStdIn = p.getOutputStream()) {
  try (InputStream pStdOut = p.getInputStream()) {
- IOUtils.writeLines(files, null, pStdIn, StandardCharsets.UTF_8);
+ IOUtils.writeLines(localFiles, null, pStdIn, StandardCharsets.UTF_8);
  pStdIn.flush();
  pStdIn.close();
  output = IOUtils.toString(pStdOut, StandardCharsets.UTF_8);
  }
  }
  log.debug("git check-ignore outputs {}", output);
 
- if (p.waitFor() != 0) {
+ final int code = p.waitFor();
+ // 0 - One or more of the provided paths is ignored.
+ // 1 - None of the provided paths are ignored.
+ // 128 - A fatal error was encountered.
+ if (code != 0 && code != 1) {
  final String error = IOUtils.toString(p.getErrorStream(), StandardCharsets.UTF_8);
- throw new Exception("git check-ignore failed:\n" + error);
+ throw new Exception("git check-ignore failed with code " + code + ":\n" + error);
  }
 
  final Stream<String> lines = Arrays.stream(output.split(System.lineSeparator()));
@@ -108,4 +116,13 @@ public void filterIgnoredFiles(Collection<String> files) {
  files.removeAll(ignoredFiles);
  log.debug("Selected files after filter ignore files: {}", files);
  }
+
+ @SneakyThrows
+ private static boolean noSymbolLink(Path path) {
+ if (path.toAbsolutePath().normalize().equals(path.toRealPath())) {
+ return true;
+ }
+ log.debug("Skip symbol link {}", path);
+ return false;
+ }
 }