Start work on the Skylark linter (skylint).

This commit introduces checking of naming conventions,
i.e. upper and lower snake case.

RELNOTES: None
PiperOrigin-RevId: 166073284

3 files changed, 112 insertions, 0 deletions

diff --git a/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/BUILD b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/BUILD
new file mode 100644
index 0000000000..61b7a8ad7c
--- /dev/null
+++ b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/BUILD
@@ -0,0 +1,23 @@
+# Tests for the Skylark linter
+
+java_test(
+    name = "SkylintTests",
+    srcs = glob(["*.java"]),
+    test_class = "com.google.devtools.skylark.skylint.SkylintTests",
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib:packages",
+        "//src/test/java/com/google/devtools/build/lib:testutil",
+        "//src/tools/skylark/java/com/google/devtools/skylark/skylint:skylint-lib",
+        "//third_party:guava",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+filegroup(
+    name = "srcs",
+    srcs = glob(
+        ["**"],
+    ),
+    visibility = ["//src:__pkg__"],
+)
diff --git a/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/NamingConventionsCheckerTest.java b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/NamingConventionsCheckerTest.java
new file mode 100644
index 0000000000..b8fefb305c
--- /dev/null
+++ b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/NamingConventionsCheckerTest.java
@@ -0,0 +1,67 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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.
+
+package com.google.devtools.skylark.skylint;
+
+import com.google.common.truth.Truth;
+import com.google.devtools.build.lib.syntax.BuildFileAST;
+import java.util.List;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Tests the lint done by {@link com.google.devtools.skylark.skylint.NamingConventionsChecker}. */
+@RunWith(JUnit4.class)
+public class NamingConventionsCheckerTest {
+  private static List<Issue> findIssues(String... lines) {
+    String content = String.join("\n", lines);
+    BuildFileAST ast =
+        BuildFileAST.parseSkylarkString(
+            event -> {
+              throw new IllegalArgumentException(event.getMessage());
+            },
+            content);
+    return NamingConventionsChecker.check(ast);
+  }
+
+  @Test
+  public void testMessages() throws Exception {
+    String errorMessage =
+        findIssues(
+                "badGlobalVariableName = 0",
+                "def badFunctionName(BadParameterName):",
+                "  BAD_LOCAL_VARIABLE_NAME = 1")
+            .toString();
+    Truth.assertThat(errorMessage)
+        .contains("'badGlobalVariableName' should be lower_snake_case or UPPER_SNAKE_CASE");
+    Truth.assertThat(errorMessage).contains("'badFunctionName' should be lower_snake_case");
+    Truth.assertThat(errorMessage).contains("'BadParameterName' should be lower_snake_case");
+    Truth.assertThat(errorMessage).contains("'BAD_LOCAL_VARIABLE_NAME' should be lower_snake_case");
+  }
+
+  @Test
+  public void testNoIssues() throws Exception {
+    Truth.assertThat(
+            findIssues(
+                "GOOD_GLOBAL_VARIABLE_NAME = 0",
+                "def good_function_name(good_parameter_name):",
+                "  good_local_variable_name = 1"))
+        .isEmpty();
+  }
+
+  @Test
+  public void testNoDuplicates() throws Exception {
+    Truth.assertThat(findIssues("def foo():", "  BAD = 1", "  BAD += 1")).hasSize(1);
+  }
+}
diff --git a/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/SkylintTests.java b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/SkylintTests.java
new file mode 100644
index 0000000000..8a1e705d6d
--- /dev/null
+++ b/src/tools/skylark/javatests/com/google/devtools/skylark/skylint/SkylintTests.java
@@ -0,0 +1,22 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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.
+
+package com.google.devtools.skylark.skylint;
+
+import com.google.devtools.build.lib.testutil.ClasspathSuite;
+import org.junit.runner.RunWith;
+
+/** All tests for skylint. */
+@RunWith(ClasspathSuite.class)
+public class SkylintTests {}