| // Copyright 2006 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.syntax.util; |
| |
| import static com.google.common.truth.Truth.assertThat; |
| import static org.junit.Assert.fail; |
| |
| import com.google.common.collect.ImmutableMap; |
| import com.google.devtools.build.lib.analysis.skylark.StarlarkModules; // a bad dependency |
| import com.google.devtools.build.lib.events.Event; |
| import com.google.devtools.build.lib.events.EventCollector; |
| import com.google.devtools.build.lib.events.EventKind; |
| import com.google.devtools.build.lib.events.ExtendedEventHandler; |
| import com.google.devtools.build.lib.events.util.EventCollectionApparatus; |
| import com.google.devtools.build.lib.packages.StarlarkSemanticsOptions; |
| import com.google.devtools.build.lib.syntax.EvalException; |
| import com.google.devtools.build.lib.syntax.EvalUtils; |
| import com.google.devtools.build.lib.syntax.Expression; |
| import com.google.devtools.build.lib.syntax.FileOptions; |
| import com.google.devtools.build.lib.syntax.Module; |
| import com.google.devtools.build.lib.syntax.Mutability; |
| import com.google.devtools.build.lib.syntax.ParserInput; |
| import com.google.devtools.build.lib.syntax.StarlarkSemantics; |
| import com.google.devtools.build.lib.syntax.StarlarkThread; |
| import com.google.devtools.build.lib.syntax.SyntaxError; |
| import com.google.devtools.common.options.Options; |
| import com.google.devtools.common.options.OptionsParsingException; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| /** Helper class for tests that evaluate Starlark code. */ |
| // TODO(adonovan): stop extending this class. Prefer composition over inheritance. |
| // Rename it to EvaluationApparatus for consistency. |
| // |
| // TODO(adonovan): make predeclared env + semantics more like normal parameters. |
| // The main challenge is when are the Thread and Module created? |
| // They should have a consistent semantics, and the predeclared environment |
| // cannot be changed after the Module is created. |
| // Also, the fact that exec/eval/update/lookup can be used directly |
| // or through a Scenario complicates the question of when we commit to |
| // predeclared env + semantics. |
| // For the most part, the predeclared env doesn't vary across a suite, |
| // so it could be a constructor parameter. |
| // |
| // TODO(adonovan): this helper class might be somewhat handy for testing core Starlark, but its |
| // widespread use in tests of Bazel features greatly hinders the improvement of Bazel's loading |
| // phase. The existence of tests based on this class forces Bazel to continue support scenarios in |
| // which the test creates the environment, the threads, and so on, when these should be |
| // implemenation details of the loading phase. Instead, the lib.packages should present an API in |
| // which the client provides files, flags, and arguments like a command-line tool, and all our tests |
| // should be ported to use that API. |
| public class EvaluationTestCase { |
| private EventCollectionApparatus eventCollectionApparatus = |
| new EventCollectionApparatus(EventKind.ALL_EVENTS); |
| |
| private StarlarkSemantics semantics = StarlarkSemantics.DEFAULT; |
| private StarlarkThread thread = null; // created lazily by getStarlarkThread |
| private Module module = null; // created lazily by getModule |
| |
| /** |
| * Parses the semantics flags and updates the semantics used to filter predeclared bindings, and |
| * carried by subsequently created threads. Causes a new StarlarkThread and Module to be created |
| * when next needed. |
| */ |
| public final void setSemantics(String... options) throws OptionsParsingException { |
| this.semantics = |
| Options.parse(StarlarkSemanticsOptions.class, options).getOptions().toStarlarkSemantics(); |
| |
| // Re-initialize the thread and module with the new semantics when needed. |
| this.thread = null; |
| this.module = null; |
| } |
| |
| public ExtendedEventHandler getEventHandler() { |
| return eventCollectionApparatus.reporter(); |
| } |
| |
| // TODO(adonovan): don't let subclasses inherit vaguely specified "helpers". |
| // Separate all the tests clearly into tests of the scanner, parser, resolver, |
| // and evaluation. |
| |
| /** Parses an expression. */ |
| protected final Expression parseExpression(String... lines) throws SyntaxError.Exception { |
| return Expression.parse(ParserInput.fromLines(lines)); |
| } |
| |
| /** Updates a global binding in the module. */ |
| // TODO(adonovan): rename setGlobal. |
| public EvaluationTestCase update(String varname, Object value) throws Exception { |
| getModule().setGlobal(varname, value); |
| return this; |
| } |
| |
| /** Returns the value of a global binding in the module. */ |
| // TODO(adonovan): rename getGlobal. |
| public Object lookup(String varname) throws Exception { |
| return getModule().getGlobal(varname); |
| } |
| |
| /** Joins the lines, parses them as an expression, and evaluates it. */ |
| public final Object eval(String... lines) throws Exception { |
| ParserInput input = ParserInput.fromLines(lines); |
| return EvalUtils.eval(input, FileOptions.DEFAULT, getModule(), getStarlarkThread()); |
| } |
| |
| /** Joins the lines, parses them as a file, and executes it. */ |
| public final void exec(String... lines) |
| throws SyntaxError.Exception, EvalException, InterruptedException { |
| ParserInput input = ParserInput.fromLines(lines); |
| EvalUtils.exec(input, FileOptions.DEFAULT, getModule(), getStarlarkThread()); |
| } |
| |
| // A hook for subclasses to alter a newly created thread, |
| // e.g. by inserting thread-local values. |
| protected void newThreadHook(StarlarkThread thread) {} |
| |
| // A hook for subclasses to alter the created module. |
| // Implementations may add to the predeclared environment, |
| // and return the module's client data value. |
| protected Object newModuleHook(ImmutableMap.Builder<String, Object> predeclared) { |
| StarlarkModules.addStarlarkGlobalsToBuilder( |
| predeclared); // TODO(adonovan): break bad dependency |
| return null; // no client data |
| } |
| |
| public StarlarkThread getStarlarkThread() { |
| if (this.thread == null) { |
| Mutability mu = Mutability.create("test"); |
| StarlarkThread thread = new StarlarkThread(mu, semantics); |
| thread.setPrintHandler(Event.makeDebugPrintHandler(getEventHandler())); |
| newThreadHook(thread); |
| this.thread = thread; |
| } |
| return this.thread; |
| } |
| |
| public Module getModule() { |
| if (this.module == null) { |
| ImmutableMap.Builder<String, Object> predeclared = ImmutableMap.builder(); |
| Object clientData = newModuleHook(predeclared); |
| Module module = Module.withPredeclared(semantics, predeclared.build()); |
| module.setClientData(clientData); |
| this.module = module; |
| } |
| return this.module; |
| } |
| |
| public void checkEvalError(String msg, String... input) throws Exception { |
| try { |
| exec(input); |
| fail("Expected error '" + msg + "' but got no error"); |
| } catch (SyntaxError.Exception | EvalException | EventCollectionApparatus.FailFastException e) { |
| assertThat(e).hasMessageThat().isEqualTo(msg); |
| } |
| } |
| |
| public void checkEvalErrorContains(String msg, String... input) throws Exception { |
| try { |
| exec(input); |
| fail("Expected error containing '" + msg + "' but got no error"); |
| } catch (SyntaxError.Exception | EvalException | EventCollectionApparatus.FailFastException e) { |
| assertThat(e).hasMessageThat().contains(msg); |
| } |
| } |
| |
| public void checkEvalErrorDoesNotContain(String msg, String... input) throws Exception { |
| try { |
| exec(input); |
| } catch (SyntaxError.Exception | EvalException | EventCollectionApparatus.FailFastException e) { |
| assertThat(e).hasMessageThat().doesNotContain(msg); |
| } |
| } |
| |
| // Forward relevant methods to the EventCollectionApparatus |
| public EvaluationTestCase setFailFast(boolean failFast) { |
| eventCollectionApparatus.setFailFast(failFast); |
| return this; |
| } |
| |
| public EvaluationTestCase assertNoWarningsOrErrors() { |
| eventCollectionApparatus.assertNoWarningsOrErrors(); |
| return this; |
| } |
| |
| public EventCollector getEventCollector() { |
| return eventCollectionApparatus.collector(); |
| } |
| |
| public Event assertContainsError(String expectedMessage) { |
| return eventCollectionApparatus.assertContainsError(expectedMessage); |
| } |
| |
| public Event assertContainsWarning(String expectedMessage) { |
| return eventCollectionApparatus.assertContainsWarning(expectedMessage); |
| } |
| |
| public Event assertContainsDebug(String expectedMessage) { |
| return eventCollectionApparatus.assertContainsDebug(expectedMessage); |
| } |
| |
| public EvaluationTestCase clearEvents() { |
| eventCollectionApparatus.clear(); |
| return this; |
| } |
| |
| /** Encapsulates a separate test which can be executed by a Scenario. */ |
| protected interface Testable { |
| void run() throws Exception; |
| } |
| |
| /** |
| * A test scenario (a script of steps). Beware: Scenario is an inner class that mutates its |
| * enclosing EvaluationTestCase as it executes the script. |
| */ |
| public final class Scenario { |
| private final SetupActions setup = new SetupActions(); |
| private final String[] starlarkOptions; |
| |
| public Scenario(String... starlarkOptions) { |
| this.starlarkOptions = starlarkOptions; |
| } |
| |
| private void run(Testable testable) throws Exception { |
| setSemantics(starlarkOptions); |
| testable.run(); |
| } |
| |
| /** Allows the execution of several statements before each following test. */ |
| public Scenario setUp(String... lines) { |
| setup.registerExec(lines); |
| return this; |
| } |
| |
| /** |
| * Allows the update of the specified variable before each following test |
| * |
| * @param name The name of the variable that should be updated |
| * @param value The new value of the variable |
| * @return This {@code Scenario} |
| */ |
| public Scenario update(String name, Object value) { |
| setup.registerUpdate(name, value); |
| return this; |
| } |
| |
| /** |
| * Evaluates two expressions and asserts that their results are equal. |
| * |
| * @param src The source expression to be evaluated |
| * @param expectedEvalString The expression of the expected result |
| * @return This {@code Scenario} |
| * @throws Exception |
| */ |
| public Scenario testEval(String src, String expectedEvalString) throws Exception { |
| runTest(createComparisonTestable(src, expectedEvalString, true)); |
| return this; |
| } |
| |
| /** Evaluates an expression and compares its result to the expected object. */ |
| public Scenario testExpression(String src, Object expected) throws Exception { |
| runTest(createComparisonTestable(src, expected, false)); |
| return this; |
| } |
| |
| /** Evaluates an expression and compares its result to the ordered list of expected objects. */ |
| public Scenario testExactOrder(String src, Object... items) throws Exception { |
| runTest(collectionTestable(src, items)); |
| return this; |
| } |
| |
| /** Evaluates an expression and checks whether it fails with the expected error. */ |
| public Scenario testIfExactError(String expectedError, String... lines) throws Exception { |
| runTest(errorTestable(true, expectedError, lines)); |
| return this; |
| } |
| |
| /** Evaluates the expresson and checks whether it fails with the expected error. */ |
| public Scenario testIfErrorContains(String expectedError, String... lines) throws Exception { |
| runTest(errorTestable(false, expectedError, lines)); |
| return this; |
| } |
| |
| /** Looks up the value of the specified variable and compares it to the expected value. */ |
| public Scenario testLookup(String name, Object expected) throws Exception { |
| runTest(createLookUpTestable(name, expected)); |
| return this; |
| } |
| |
| /** |
| * Creates a Testable that checks whether the evaluation of the given expression fails with the |
| * expected error. |
| * |
| * @param exactMatch whether the error message must be identical to the expected error. |
| */ |
| private Testable errorTestable( |
| final boolean exactMatch, final String error, final String... lines) { |
| return new Testable() { |
| @Override |
| public void run() throws Exception { |
| if (exactMatch) { |
| checkEvalError(error, lines); |
| } else { |
| checkEvalErrorContains(error, lines); |
| } |
| } |
| }; |
| } |
| |
| /** |
| * Creates a Testable that checks whether the value of the expression is a sequence containing |
| * the expected elements. |
| */ |
| private Testable collectionTestable(final String src, final Object... expected) { |
| return new Testable() { |
| @Override |
| public void run() throws Exception { |
| assertThat((Iterable<?>) eval(src)).containsExactly(expected).inOrder(); |
| } |
| }; |
| } |
| |
| /** |
| * Creates a testable that compares the value of the expression to a specified result. |
| * |
| * @param src The expression to be evaluated |
| * @param expected Either the expected object or an expression whose evaluation leads to the |
| * expected object |
| * @param expectedIsExpression Signals whether {@code expected} is an object or an expression |
| * @return An instance of Testable that runs the comparison |
| */ |
| private Testable createComparisonTestable( |
| final String src, final Object expected, final boolean expectedIsExpression) { |
| return new Testable() { |
| @Override |
| public void run() throws Exception { |
| Object actual = eval(src); |
| Object realExpected = expected; |
| |
| // We could also print the actual object and compare the string to the expected |
| // expression, but then the order of elements would matter. |
| if (expectedIsExpression) { |
| realExpected = eval((String) expected); |
| } |
| |
| assertThat(actual).isEqualTo(realExpected); |
| } |
| }; |
| } |
| |
| /** |
| * Creates a Testable that looks up the given variable and compares its value to the expected |
| * value |
| * |
| * @param name |
| * @param expected |
| * @return An instance of Testable that does both lookup and comparison |
| */ |
| private Testable createLookUpTestable(final String name, final Object expected) { |
| return new Testable() { |
| @Override |
| public void run() throws Exception { |
| assertThat(lookup(name)).isEqualTo(expected); |
| } |
| }; |
| } |
| |
| /** |
| * Executes the given Testable |
| * @param testable |
| * @throws Exception |
| */ |
| protected void runTest(Testable testable) throws Exception { |
| run(new TestableDecorator(setup, testable)); |
| } |
| } |
| |
| /** |
| * A simple decorator that allows the execution of setup actions before running a {@code Testable} |
| */ |
| static class TestableDecorator implements Testable { |
| private final SetupActions setup; |
| private final Testable decorated; |
| |
| public TestableDecorator(SetupActions setup, Testable decorated) { |
| this.setup = setup; |
| this.decorated = decorated; |
| } |
| |
| /** |
| * Executes all stored actions and updates plus the actual {@code Testable} |
| */ |
| @Override |
| public void run() throws Exception { |
| setup.executeAll(); |
| decorated.run(); |
| } |
| } |
| |
| /** |
| * A container for collection actions that should be executed before a test |
| */ |
| class SetupActions { |
| private List<Testable> setup; |
| |
| public SetupActions() { |
| setup = new LinkedList<>(); |
| } |
| |
| /** |
| * Registers an update to a module variable to be bound before a test |
| * |
| * @param name |
| * @param value |
| */ |
| public void registerUpdate(final String name, final Object value) { |
| setup.add( |
| new Testable() { |
| @Override |
| public void run() throws Exception { |
| EvaluationTestCase.this.update(name, value); |
| } |
| }); |
| } |
| |
| /** Registers a sequence of statements for execution prior to a test. */ |
| public void registerExec(final String... lines) { |
| setup.add( |
| new Testable() { |
| @Override |
| public void run() throws Exception { |
| EvaluationTestCase.this.exec(lines); |
| } |
| }); |
| } |
| |
| /** |
| * Executes all stored actions and updates |
| * @throws Exception |
| */ |
| public void executeAll() throws Exception { |
| for (Testable testable : setup) { |
| testable.run(); |
| } |
| } |
| } |
| } |