[clang-tools-extra] [llvm] [llvm] add support for mustache templating language (PR #105893)

[Paul Kirth via cfe-commits]

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@@ -0,0 +1,135 @@
+//===- llvm/unittest/Support/MustacheTest.cpp ----------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Test conforming to Mustache 1.4.2 spec found here:
+// https://github.com/mustache/spec
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Mustache.h"
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace llvm::mustache;
+using namespace llvm::json;
+
+TEST(MustacheInterpolation, NoInterpolation) {
+  // Mustache-free templates should render as-is.
+  Value D = {};
+  auto T = Template::createTemplate("Hello from {Mustache}!\n");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("Hello from {Mustache}!\n", Out);
+}
+
+TEST(MustacheInterpolation, BasicInterpolation) {
+  // Unadorned tags should interpolate content into the template.
+  Value D = Object{{"subject", "World"}};
+  auto T = Template::createTemplate("Hello, {{subject}}!");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("Hello, World!", Out);
+}
+
+TEST(MustacheInterpolation, NoReinterpolation) {
+  // Interpolated tag output should not be re-interpolated.
+  Value D = Object{{"template", "{{planet}}"}, {"planet", "Earth"}};
+  auto T = Template::createTemplate("{{template}}: {{planet}}");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("{{planet}}: Earth", Out);
+}
+
+TEST(MustacheInterpolation, HTMLEscaping) {
+  // Interpolated tag output should not be re-interpolated.
+  Value D = Object{
+      {"forbidden", "& \" < >"},
+  };
+  auto T = Template::createTemplate(
+      "These characters should be HTML escaped: {{forbidden}}\n");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("These characters should be HTML escaped: & " < >\n",
+            Out);
+}
+
+TEST(MustacheInterpolation, Ampersand) {
+  // Interpolated tag output should not be re-interpolated.
+  Value D = Object{
+      {"forbidden", "& \" < >"},
+  };
+  auto T = Template::createTemplate(
+      "These characters should not be HTML escaped: {{&forbidden}}\n");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("These characters should not be HTML escaped: & \" < >\n", Out);
+}
+
+TEST(MustacheInterpolation, BasicIntegerInterpolation) {
+  Value D = Object{{"mph", 85}};
+  auto T = Template::createTemplate("{{mph}} miles an hour!");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("85 miles an hour!", Out);
+}
+
+TEST(MustacheInterpolation, BasicDecimalInterpolation) {
+  Value D = Object{{"power", 1.21}};
+  auto T = Template::createTemplate("{{power}} jiggawatts!");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("1.21 jiggawatts!", Out);
+}
+
+TEST(MustacheInterpolation, BasicNullInterpolation) {
+  Value D = Object{{"cannot", nullptr}};
+  auto T = Template::createTemplate("I ({{cannot}}) be seen!");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("I () be seen!", Out);
+}
+
+TEST(MustacheInterpolation, BasicContextMissInterpolation) {
+  Value D = Object{};
+  auto T = Template::createTemplate("I ({{cannot}}) be seen!");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("I () be seen!", Out);
+}
+
+TEST(MustacheInterpolation, DottedNamesBasicInterpolation) {
+  Value D = Object{{"person", Object{{"name", "Joe"}}}};
+  auto T = Template::createTemplate(
+      "{{person.name}} == {{#person}}{{name}}{{/person}}");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("Joe == Joe", Out);
+}
+
+TEST(MustacheInterpolation, DottedNamesArbitraryDepth) {
+  Value D = Object{
+      {"a",
+       Object{{"b",
+               Object{{"c",
+                       Object{{"d",
+                               Object{{"e", Object{{"name", "Phil"}}}}}}}}}}}};
+  auto T = Template::createTemplate("{{a.b.c.d.e.name}} == Phil");
+  auto Out = T.get().render(D);
+  EXPECT_EQ("Phil == Phil", Out);
----------------
ilovepi wrote:

I don't think you need the `== Phil` bits, do you? It seems redundant, since you just want it to match, right?

https://github.com/llvm/llvm-project/pull/105893