Add a dependency fixer for proto deps

protoc dependency files, at least for C++ outputs, uses the form of:

  a/b.c \
  a/b.h: <dep1> <dep2>...

Ninja will fail the command when it parses a dep file and there's more
than one output file (even though it doesn't care what the output file
name is). So this tool will parse the original file, and output a
version with only a single output file.

Bug: 67329638
Test: NINJA_ARGS="-t deps ...pb.c" m
Test: NINJA_ARGS="-t deps ...srcjar" m
Test: NINJA_ARGS="-t deps ...srcszip" m
Test: Run dep_fixer across all of taimen's dep files, no failures.
Test: Run dep_fixer against the processed files, no changes.
Test: Run androidmk across all of our Android.mk files, inspect the diffs
Change-Id: I4263b7d5faea37285afa6b24dedf5964aa7d19dc

1 files changed, 72 insertions, 0 deletions

diff --git a/androidmk/parser/make_strings_test.go b/androidmk/parser/make_strings_test.go
index 8ad3d74c..6995e891 100644
--- a/androidmk/parser/make_strings_test.go
+++ b/androidmk/parser/make_strings_test.go
@@ -99,6 +99,78 @@ func TestMakeStringSplitN(t *testing.T) {
 	}
 }
 
+var valueTestCases = []struct {
+	in       *MakeString
+	expected string
+}{
+	{
+		in:       SimpleMakeString("a b", NoPos),
+		expected: "a b",
+	},
+	{
+		in:       SimpleMakeString("a\\ \\\tb\\\\", NoPos),
+		expected: "a \tb\\",
+	},
+	{
+		in:       SimpleMakeString("a\\b\\", NoPos),
+		expected: "a\\b\\",
+	},
+}
+
+func TestMakeStringValue(t *testing.T) {
+	for _, test := range valueTestCases {
+		got := test.in.Value(nil)
+		if got != test.expected {
+			t.Errorf("\nwith: %q\nwant: %q\n got: %q", test.in.Dump(), test.expected, got)
+		}
+	}
+}
+
+var splitWordsTestCases = []struct {
+	in       *MakeString
+	expected []*MakeString
+}{
+	{
+		in:       SimpleMakeString("", NoPos),
+		expected: []*MakeString{},
+	},
+	{
+		in: SimpleMakeString(" a b\\ c d", NoPos),
+		expected: []*MakeString{
+			SimpleMakeString("a", NoPos),
+			SimpleMakeString("b\\ c", NoPos),
+			SimpleMakeString("d", NoPos),
+		},
+	},
+	{
+		in: SimpleMakeString("  a\tb\\\t\\ c d  ", NoPos),
+		expected: []*MakeString{
+			SimpleMakeString("a", NoPos),
+			SimpleMakeString("b\\\t\\ c", NoPos),
+			SimpleMakeString("d", NoPos),
+		},
+	},
+	{
+		in: SimpleMakeString(`a\\ b\\\ c d`, NoPos),
+		expected: []*MakeString{
+			SimpleMakeString(`a\\`, NoPos),
+			SimpleMakeString(`b\\\ c`, NoPos),
+			SimpleMakeString("d", NoPos),
+		},
+	},
+}
+
+func TestMakeStringWords(t *testing.T) {
+	for _, test := range splitWordsTestCases {
+		got := test.in.Words()
+		gotString := dumpArray(got)
+		expectedString := dumpArray(test.expected)
+		if gotString != expectedString {
+			t.Errorf("with:\n%q\nexpected:\n%s\ngot:\n%s", test.in.Dump(), expectedString, gotString)
+		}
+	}
+}
+
 func dumpArray(a []*MakeString) string {
 	ret := make([]string, len(a))