utils: Add ReplaceAll() string helper

Helpful for template string substitutions in tests, to reduce string concat noise.

Change-Id: I612084e2c267d93d79c92cf3ac0231b6b904f0e3
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/66440
Commit-Queue: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>

src/BUILD.gn

@@ -481,6 +481,7 @@ libtint_source_set("libtint_core_all_src") {
     "utils/hash.h",
     "utils/math.h",
     "utils/scoped_assignment.h",
+    "utils/string.h",
     "utils/unique_vector.h",
     "writer/append_vector.cc",
     "writer/append_vector.h",

src/CMakeLists.txt

@@ -391,6 +391,7 @@ set(TINT_LIB_SRCS
   utils/hash.h
   utils/math.h
   utils/scoped_assignment.h
+  utils/string.h
   utils/unique_vector.h
   writer/append_vector.cc
   writer/append_vector.h
@@ -722,6 +723,7 @@ if(${TINT_BUILD_TESTS})
     utils/math_test.cc
     utils/reverse_test.cc
     utils/scoped_assignment_test.cc
+    utils/string_test.cc
     utils/unique_vector_test.cc
     writer/append_vector_test.cc
     writer/float_to_string_test.cc

src/utils/string.h

@@ -0,0 +1,41 @@
+// Copyright 2021 The Tint Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef SRC_UTILS_STRING_H_
+#define SRC_UTILS_STRING_H_
+
+#include <string>
+
+namespace tint {
+namespace utils {
+
+/// @param str the string to apply replacements to
+/// @param substr the string to search for
+/// @param replacement the replacement string to use instead of `substr`
+/// @returns `str` with all occurrances of `substr` replaced with `replacement`
+inline std::string ReplaceAll(std::string str,
+                              const std::string& substr,
+                              const std::string& replacement) {
+  size_t pos = 0;
+  while ((pos = str.find(substr, pos)) != std::string::npos) {
+    str.replace(pos, substr.length(), replacement);
+    pos += replacement.length();
+  }
+  return str;
+}
+
+}  // namespace utils
+}  // namespace tint
+
+#endif  //  SRC_UTILS_STRING_H_

src/utils/string_test.cc

@@ -0,0 +1,34 @@
+// Copyright 2021 The Tint Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "src/utils/string.h"
+
+#include "gtest/gtest.h"
+
+namespace tint {
+namespace utils {
+namespace {
+
+TEST(StringTest, ReplaceAll) {
+  ASSERT_EQ("xybbcc", ReplaceAll("aabbcc", "aa", "xy"));
+  ASSERT_EQ("aaxycc", ReplaceAll("aabbcc", "bb", "xy"));
+  ASSERT_EQ("aabbxy", ReplaceAll("aabbcc", "cc", "xy"));
+  ASSERT_EQ("xyxybbcc", ReplaceAll("aabbcc", "a", "xy"));
+  ASSERT_EQ("aaxyxycc", ReplaceAll("aabbcc", "b", "xy"));
+  ASSERT_EQ("aabbxyxy", ReplaceAll("aabbcc", "c", "xy"));
+}
+
+}  // namespace
+}  // namespace utils
+}  // namespace tint

test/BUILD.gn

@@ -323,6 +323,7 @@ tint_unittests_source_set("tint_unittests_core_src") {
     "../src/utils/math_test.cc",
     "../src/utils/reverse_test.cc",
     "../src/utils/scoped_assignment_test.cc",
+    "../src/utils/string_test.cc",
     "../src/utils/unique_vector_test.cc",
     "../src/writer/append_vector_test.cc",
     "../src/writer/float_to_string_test.cc",