[clang-format] Add option to explicitly specify a config file

This diff extends the -style=file option to allow a config file to be specified explicitly. This is useful (for instance) when adding IDE commands to reformat code to a personal style.

Usage: `clang-format -style=file:<path/to/config/file> ...`

Reviewed By: HazardyKnusperkeks, curdeius, MyDeveloperDay, zwliew

Differential Revision: https://reviews.llvm.org/D72326

1 files changed, 64 insertions, 0 deletions

diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index bb344d4..7160c7a 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -21579,6 +21579,70 @@ TEST(FormatStyle, GetStyleOfFile) {
     Style.IndentWidth = 7;
     return Style;
   }());
+
+  // Test 9.9: use inheritance from a specific config file.
+  Style9 = getStyle("file:/e/sub/sub/.clang-format", "/e/sub/sub/code.cpp",
+                    "none", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style9));
+  ASSERT_EQ(*Style9, SubSubStyle);
+}
+
+TEST(FormatStyle, GetStyleOfSpecificFile) {
+  llvm::vfs::InMemoryFileSystem FS;
+  // Specify absolute path to a format file in a parent directory.
+  ASSERT_TRUE(
+      FS.addFile("/e/.clang-format", 0,
+                 llvm::MemoryBuffer::getMemBuffer("BasedOnStyle: LLVM")));
+  ASSERT_TRUE(
+      FS.addFile("/e/explicit.clang-format", 0,
+                 llvm::MemoryBuffer::getMemBuffer("BasedOnStyle: Google")));
+  ASSERT_TRUE(FS.addFile("/e/sub/sub/sub/test.cpp", 0,
+                         llvm::MemoryBuffer::getMemBuffer("int i;")));
+  auto Style = getStyle("file:/e/explicit.clang-format",
+                        "/e/sub/sub/sub/test.cpp", "LLVM", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style));
+  ASSERT_EQ(*Style, getGoogleStyle());
+
+  // Specify relative path to a format file.
+  ASSERT_TRUE(
+      FS.addFile("../../e/explicit.clang-format", 0,
+                 llvm::MemoryBuffer::getMemBuffer("BasedOnStyle: Google")));
+  Style = getStyle("file:../../e/explicit.clang-format",
+                   "/e/sub/sub/sub/test.cpp", "LLVM", "", &FS);
+  ASSERT_TRUE(static_cast<bool>(Style));
+  ASSERT_EQ(*Style, getGoogleStyle());
+
+  // Specify path to a format file that does not exist.
+  Style = getStyle("file:/e/missing.clang-format", "/e/sub/sub/sub/test.cpp",
+                   "LLVM", "", &FS);
+  ASSERT_FALSE(static_cast<bool>(Style));
+  llvm::consumeError(Style.takeError());
+
+  // Specify path to a file on the filesystem.
+  SmallString<128> FormatFilePath;
+  std::error_code ECF = llvm::sys::fs::createTemporaryFile(
+      "FormatFileTest", "tpl", FormatFilePath);
+  EXPECT_FALSE((bool)ECF);
+  llvm::raw_fd_ostream FormatFileTest(FormatFilePath, ECF);
+  EXPECT_FALSE((bool)ECF);
+  FormatFileTest << "BasedOnStyle: Google\n";
+  FormatFileTest.close();
+
+  SmallString<128> TestFilePath;
+  std::error_code ECT =
+      llvm::sys::fs::createTemporaryFile("CodeFileTest", "cc", TestFilePath);
+  EXPECT_FALSE((bool)ECT);
+  llvm::raw_fd_ostream CodeFileTest(TestFilePath, ECT);
+  CodeFileTest << "int i;\n";
+  CodeFileTest.close();
+
+  std::string format_file_arg = std::string("file:") + FormatFilePath.c_str();
+  Style = getStyle(format_file_arg, TestFilePath, "LLVM", "", nullptr);
+
+  llvm::sys::fs::remove(FormatFilePath.c_str());
+  llvm::sys::fs::remove(TestFilePath.c_str());
+  ASSERT_TRUE(static_cast<bool>(Style));
+  ASSERT_EQ(*Style, getGoogleStyle());
 }
 
 TEST_F(ReplacementTest, FormatCodeAfterReplacements) {