Fix bug when processing parent gitignore files.

This particular bug was triggered whenever a search was run in a directory
with a parent directory that contains a relevant .gitignore file. In
particular, before matching against a parent directory's gitignore rules,
a path's leading `./` was not stripped, which results in errant matching.

We now make sure `./` is stripped.

Fixes #184.

src/ignore.rs

@@ -20,7 +20,7 @@ use std::io;
 use std::path::{Path, PathBuf};
 
 use gitignore::{self, Gitignore, GitignoreBuilder, Match, Pattern};
-use pathutil::{file_name, is_hidden};
+use pathutil::{file_name, is_hidden, strip_prefix};
 use types::Types;
 
 const IGNORE_NAMES: &'static [&'static str] = &[
@@ -222,7 +222,10 @@ impl Ignore {
 
     /// Returns true if and only if the given file path should be ignored.
     pub fn ignored<P: AsRef<Path>>(&self, path: P, is_dir: bool) -> bool {
-        let path = path.as_ref();
+        let mut path = path.as_ref();
+        if let Some(p) = strip_prefix("./", path) {
+            path = p;
+        }
         let mat = self.overrides.matched(path, is_dir);
         if let Some(is_ignored) = self.ignore_match(path, mat) {
             return is_ignored;

tests/tests.rs

@@ -837,6 +837,20 @@ clean!(
     assert_eq!(lines, TESTCASE);
 });
 
+// See: https://github.com/BurntSushi/ripgrep/issues/184
+clean!(regression_184, "test", ".", |wd: WorkDir, mut cmd: Command| {
+    wd.create(".gitignore", ".*");
+    wd.create_dir("foo/bar");
+    wd.create("foo/bar/baz", "test");
+
+    let lines: String = wd.stdout(&mut cmd);
+    assert_eq!(lines, format!("{}:test\n", path("foo/bar/baz")));
+
+    cmd.current_dir(wd.path().join("./foo/bar"));
+    let lines: String = wd.stdout(&mut cmd);
+    assert_eq!(lines, "baz:test\n");
+});
+
 // See: https://github.com/BurntSushi/ripgrep/issues/20
 sherlock!(feature_20_no_filename, "Sherlock", ".",
 |wd: WorkDir, mut cmd: Command| {