Add a builder-like mechanism for writing targets to a Scratch instance that is

usable across front-end types.

--
MOS_MIGRATED_REVID=129633711

3 files changed, 245 insertions, 15 deletions

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewTestCase.java b/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewTestCase.java
index 4fdde18aab..8f80ee614d 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewTestCase.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewTestCase.java
@@ -669,12 +669,12 @@ public abstract class BuildViewTestCase extends FoundationTestCase {
   }
 
   /**
-   * Returns the ConfiguredTarget for the specified label, configured for the
-   * "build" (aka "target") configuration.
+   * Returns the ConfiguredTarget for the specified label, configured for the "build" (aka "target")
+   * configuration.
    */
-  protected ConfiguredTarget getConfiguredTarget(String label)
-      throws NoSuchPackageException, NoSuchTargetException,
-      LabelSyntaxException, InterruptedException {
+  public ConfiguredTarget getConfiguredTarget(String label)
+      throws NoSuchPackageException, NoSuchTargetException, LabelSyntaxException,
+          InterruptedException {
     return getConfiguredTarget(label, targetConfig);
   }
 
diff --git a/src/test/java/com/google/devtools/build/lib/analysis/util/ScratchAttributeWriter.java b/src/test/java/com/google/devtools/build/lib/analysis/util/ScratchAttributeWriter.java
new file mode 100644
index 0000000000..bec2ce7c2b
--- /dev/null
+++ b/src/test/java/com/google/devtools/build/lib/analysis/util/ScratchAttributeWriter.java
@@ -0,0 +1,226 @@
+// Copyright 2016 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.build.lib.analysis.util;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.testutil.Scratch;
+import java.io.IOException;
+import java.util.Arrays;
+
+/**
+ * A writer for a scratch build target and associated source files. Can be parameterized with a rule
+ * type for which to write a mock target.
+ *
+ * <p>For example, the snippet:
+ *
+ * <pre>{@code
+ * new ScratchAttributeWriter(testCase, "cc_library", "//x:x")
+ *     .setList("srcs", "a.cc", "b.cc")
+ *     .setList("hdrs", "hdr.h")
+ *     .write();
+ * }</pre>
+ *
+ * <p>Would create the BUILD file "x/BUILD" with contents:
+ *
+ * <pre>{@code
+ * cc_library(
+ *     name = 'x',
+ *     srcs = ['a.cc', 'b.cc'],
+ *     hdrs = ['hdr.h'],
+ * )
+ * }</pre>
+ */
+public class ScratchAttributeWriter {
+
+  private abstract static class ScratchAttribute<T> {
+    protected String attributeName;
+    protected T attributeValue;
+
+    abstract StringBuilder appendLine(StringBuilder builder);
+  }
+
+  /** A plain string attribute. */
+  private static class StringAttribute extends ScratchAttribute<String> {
+    public StringAttribute(String attributeName, String attributeValue) {
+      this.attributeName = attributeName;
+      this.attributeValue = attributeValue;
+    }
+
+    @Override
+    StringBuilder appendLine(StringBuilder builder) {
+      return builder.append(String.format("%s=%s,", attributeName, attributeValue));
+    }
+  }
+
+  /** An integer attribute, such as "alwayslink" */
+  private static class IntegerAttribute extends ScratchAttribute<Integer> {
+
+    public IntegerAttribute(String attributeName, Integer attributeValue) {
+      this.attributeName = attributeName;
+      this.attributeValue = attributeValue;
+    }
+
+    @Override
+    StringBuilder appendLine(StringBuilder builder) {
+      return builder.append(String.format("%s=%d,", attributeName, attributeValue));
+    }
+  }
+
+  /** A list attribute, such as "srcs" */
+  private static class StringListAttribute extends ScratchAttribute<Iterable<String>> {
+
+    public StringListAttribute(String attributeName, Iterable<String> attributeValue) {
+      this.attributeName = attributeName;
+      this.attributeValue = attributeValue;
+    }
+
+    @Override
+    StringBuilder appendLine(StringBuilder builder) {
+      builder.append(String.format("%s=[", attributeName));
+      for (String value : attributeValue) {
+        builder.append(String.format("'%s',", value));
+      }
+      builder.append("],");
+      return builder;
+    }
+  }
+
+  /** The name of the package. */
+  private final String packageName;
+
+  /** The name of the target. */
+  private final String targetName;
+
+  /** The test case for which to write this target. */
+  private final BuildViewTestCase testCase;
+
+  /** The name of the rule for this target */
+  private final String ruleName;
+
+  /** An ordered list of the attributes to be written for this scratch target */
+  StringBuilder buildString;
+
+  /**
+   * Creates a ScratchAttributeWriter for a given test case, package name, and target name. The
+   * provided rule name will determine the type of the target written.
+   */
+  private ScratchAttributeWriter(
+      BuildViewTestCase testCase, String ruleName, String packageName, String targetName) {
+    this.testCase = checkNotNull(testCase);
+    this.ruleName = checkNotNull(ruleName);
+    this.packageName = checkNotNull(packageName);
+    this.targetName = checkNotNull(targetName);
+    this.buildString =
+        new StringBuilder()
+            .append(String.format("%s(", this.ruleName))
+            .append(String.format("name='%s',", this.targetName));
+  }
+
+  /**
+   * Creates a ScratchAttributeWriter for a given test case and label. The provided rule name will
+   * determine the type of the target written.
+   */
+  public static ScratchAttributeWriter fromLabel(
+      BuildViewTestCase testCase, String ruleName, Label label) {
+    return new ScratchAttributeWriter(testCase, ruleName, label.getPackageName(), label.getName());
+  }
+
+  /**
+   * Creates a ScratchAttributeWriter for a given test case and label string. The provided rule name
+   * will determine the type of the target written.
+   */
+  public static ScratchAttributeWriter fromLabelString(
+      BuildViewTestCase testCase, String ruleName, String labelString) {
+    return fromLabel(testCase, ruleName, Label.parseAbsoluteUnchecked(labelString));
+  }
+
+  /**
+   * Writes this scratch target to this ScratchAttributeWriter's Scratch instance, and returns the
+   * target in the given configuration.
+   */
+  public ConfiguredTarget write(BuildConfiguration config) throws Exception {
+    Scratch scratch = testCase.getScratch();
+
+    buildString.append(")");
+
+    scratch.file(String.format("%s/BUILD", packageName), buildString.toString());
+    return testCase.getConfiguredTarget(String.format("//%s:%s", packageName, targetName), config);
+  }
+
+  /**
+   * Writes this scratch target to this ScratchAttributeWriter's Scratch instance, and returns the
+   * target in the target configuration.
+   */
+  public ConfiguredTarget write() throws Exception {
+    return write(testCase.getTargetConfiguration());
+  }
+
+  private void createSource(String source) throws IOException {
+    testCase.getScratch().file(String.format("%s/%s", packageName, source));
+  }
+
+  /** Sets a string attribute (like ios_application.app_icon) for this target. */
+  public ScratchAttributeWriter set(String name, String value) {
+    new StringAttribute(name, value).appendLine(this.buildString);
+    return this;
+  }
+
+  /** Sets a list attribute (like cc_library.srcs) for this target. */
+  public ScratchAttributeWriter setList(String name, Iterable<String> value) {
+    new StringListAttribute(name, value).appendLine(this.buildString);
+    return this;
+  }
+
+  /** Sets a list attribute (like cc_library.srcs) for this target */
+  public ScratchAttributeWriter setList(String name, String... value) {
+    return setList(name, Arrays.asList(value));
+  }
+
+  /** Sets an integer attribute (like cc_binary.linkstatic) for this target. */
+  public ScratchAttributeWriter set(String name, int value) {
+    new IntegerAttribute(name, value).appendLine(this.buildString);
+    return this;
+  }
+
+  /**
+   * Sets a list attribute (link cc_library.srcs) for this target. For each string in 'value',
+   * writes an empty file to this writer's package with that name.
+   *
+   * <p>Usually, an analysis-time should not require that referenced files actually be written, in
+   * which case ScratchAttributeWriter#set should be used instead.
+   */
+  public ScratchAttributeWriter setAndCreateFiles(String name, Iterable<String> value)
+      throws IOException {
+    for (String source : value) {
+      createSource(source);
+    }
+    return setList(name, value);
+  }
+
+  /**
+   * Sets a list attribute (link cc_library.srcs) for this target. For each string in 'value',
+   * writes an empty file to this writer's package with that name.
+   *
+   * <p>Usually, an analysis-time should not require that referenced files actually be written, in
+   * which case ScratchAttributeWriter#set should be used instead.
+   */
+  public ScratchAttributeWriter setAndCreateFiles(String name, String... value) throws IOException {
+    return setAndCreateFiles(name, Arrays.asList(value));
+  }
+}
diff --git a/src/test/java/com/google/devtools/build/lib/testutil/FoundationTestCase.java b/src/test/java/com/google/devtools/build/lib/testutil/FoundationTestCase.java
index 689b822878..098a4dd5c6 100644
--- a/src/test/java/com/google/devtools/build/lib/testutil/FoundationTestCase.java
+++ b/src/test/java/com/google/devtools/build/lib/testutil/FoundationTestCase.java
@@ -24,12 +24,10 @@ import com.google.devtools.build.lib.util.BlazeClock;
 import com.google.devtools.build.lib.vfs.FileSystem;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.lib.vfs.inmemoryfs.InMemoryFileSystem;
-
+import java.util.Set;
 import org.junit.After;
 import org.junit.Before;
 
-import java.util.Set;
-
 /**
  * A helper class for implementing tests of the "foundation" library.
  */
@@ -42,16 +40,22 @@ public abstract class FoundationTestCase {
   protected EventCollector eventCollector;
   protected Scratch scratch;
 
+  /** Returns the Scratch instance for this test case. */
+  public Scratch getScratch() {
+    return scratch;
+  }
+
   // Individual tests can opt-out of this handler if they expect an error, by
   // calling reporter.removeHandler(failFastHandler).
-  protected static final EventHandler failFastHandler = new EventHandler() {
-      @Override
-      public void handle(Event event) {
-        if (EventKind.ERRORS.contains(event.getKind())) {
-          fail(event.toString());
+  protected static final EventHandler failFastHandler =
+      new EventHandler() {
+        @Override
+        public void handle(Event event) {
+          if (EventKind.ERRORS.contains(event.getKind())) {
+            fail(event.toString());
+          }
         }
-      }
-    };
+      };
 
   protected static final EventHandler printHandler = new EventHandler() {
       @Override