src/test/java/com/google/devtools/build/lib/syntax/StarlarkThreadDebuggingTest.java - bazel - Git at Google

 // Copyright 2018 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;

 import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertThrows;

 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.syntax.Debug.ReadyToPause;
 import com.google.devtools.build.lib.syntax.Debug.Stepping;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

 /** Tests of debugging features of StarlarkThread. */
 @RunWith(JUnit4.class)
 public class StarlarkThreadDebuggingTest {

   // TODO(adonovan): rewrite these tests at a higher level.

   private static StarlarkThread newThread() {
     return new StarlarkThread(Mutability.create("test"), StarlarkSemantics.DEFAULT);
   }

   // Executes the definition of a trivial function f and returns the function value.
   private static StarlarkFunction defineFunc() throws Exception {
     return (StarlarkFunction)
         Starlark.execFile(
             ParserInput.fromLines("def f(): pass\nf"),
             FileOptions.DEFAULT,
             Module.create(),
             newThread());
   }

   @Test
   public void testListFramesEmptyStack() throws Exception {
     StarlarkThread thread = newThread();
     assertThat(Debug.getCallStack(thread)).isEmpty();
     assertThat(thread.getCallStack()).isEmpty();
   }

   @Test
   public void testListFramesFromBuiltin() throws Exception {
     // f is a built-in that captures the stack using the Debugger API.
     Object[] result = {null, null};
     StarlarkCallable f =
         new StarlarkCallable() {
           @Override
           public String getName() {
             return "f";
           }

           @Override
           public Object fastcall(StarlarkThread thread, Object[] positional, Object[] named) {
             result[0] = Debug.getCallStack(thread);
             result[1] = thread.getCallStack();
             return Starlark.NONE;
           }

           @Override
           public Location getLocation() {
             return Location.fromFileLineColumn("builtin", 12, 0);
           }

           @Override
           public String toString() {
             return "<debug function>";
           }
         };

     // Set up global environment.
     Module module =
         Module.withPredeclared(StarlarkSemantics.DEFAULT, ImmutableMap.of("a", 1, "b", 2, "f", f));

     // Execute a small file that calls f.
     ParserInput input =
         ParserInput.fromString(
             "def g(a, y, z):\n" // shadows global a
                 + "  f()\n"
                 + "g(4, 5, 6)",
             "main.star");
     Starlark.execFile(input, FileOptions.DEFAULT, module, newThread());

     @SuppressWarnings("unchecked")
     ImmutableList<Debug.Frame> stack = (ImmutableList<Debug.Frame>) result[0];

     // Check the stack captured by f.
     // We compare printed string forms, as it gives more informative assertion failures.
     StringBuilder buf = new StringBuilder();
     for (Debug.Frame fr : stack) {
       buf.append(
           String.format(
               "%s @ %s local=%s\n", fr.getFunction().getName(), fr.getLocation(), fr.getLocals()));
     }
     assertThat(buf.toString())
         .isEqualTo(
             ""
                 // location is paren of g(4, 5, 6) call:
                 + "<toplevel> @ main.star:3:2 local={}\n"
                 // location is paren of "f()" call:
                 + "g @ main.star:2:4 local={a=4, y=5, z=6}\n"
                 // location is "current PC" in f.
                 + "f @ builtin:12 local={}\n");

     // Same, with "lite" stack API.
     assertThat(result[1].toString()) // an ImmutableList<StarlarkThread.CallStackEntry>
         .isEqualTo("[<toplevel>@main.star:3:2, g@main.star:2:4, f@builtin:12]");

     // TODO(adonovan): more tests:
     // - a stack containing functions defined in different modules.
     // - changing environment at various program points within a function.
   }

   @Test
   public void testStepIntoFunction() throws Exception {
     StarlarkThread thread = newThread();

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);
     thread.push(defineFunc());

     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepIntoFallsBackToStepOver() {
     // test that when stepping into, we'll fall back to stopping at the next statement in the
     // current frame
     StarlarkThread thread = newThread();

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);

     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepIntoFallsBackToStepOut() throws Exception {
     // test that when stepping into, we'll fall back to stopping when exiting the current frame
     StarlarkThread thread = newThread();
     thread.push(defineFunc());

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);
     thread.pop();

     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepOverFunction() throws Exception {
     StarlarkThread thread = newThread();

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.OVER);
     thread.push(defineFunc());

     assertThat(predicate.test(thread)).isFalse();
     thread.pop();
     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepOverFallsBackToStepOut() throws Exception {
     // test that when stepping over, we'll fall back to stopping when exiting the current frame
     StarlarkThread thread = newThread();
     thread.push(defineFunc());

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.OVER);
     thread.pop();

     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepOutOfInnerFrame() throws Exception {
     StarlarkThread thread = newThread();
     thread.push(defineFunc());

     ReadyToPause predicate = Debug.stepControl(thread, Stepping.OUT);

     assertThat(predicate.test(thread)).isFalse();
     thread.pop();
     assertThat(predicate.test(thread)).isTrue();
   }

   @Test
   public void testStepOutOfOutermostFrame() {
     StarlarkThread thread = newThread();

     assertThat(Debug.stepControl(thread, Stepping.OUT)).isNull();
   }

   @Test
   public void testStepControlWithNoSteppingReturnsNull() {
     StarlarkThread thread = newThread();

     assertThat(Debug.stepControl(thread, Stepping.NONE)).isNull();
   }

   @Test
   public void testEvaluateVariableInScope() throws Exception {
     Module module = Module.withPredeclared(StarlarkSemantics.DEFAULT, ImmutableMap.of("a", 1));

     StarlarkThread thread = newThread();
     Object a = Starlark.execFile(ParserInput.fromLines("a"), FileOptions.DEFAULT, module, thread);
     assertThat(a).isEqualTo(1);
   }

   @Test
   public void testEvaluateVariableNotInScopeFails() throws Exception {
     Module module = Module.create();

     SyntaxError.Exception e =
         assertThrows(
             SyntaxError.Exception.class,
             () ->
                 Starlark.execFile(
                     ParserInput.fromLines("b"), FileOptions.DEFAULT, module, newThread()));

     assertThat(e).hasMessageThat().isEqualTo("name 'b' is not defined");
   }

   @Test
   public void testEvaluateExpressionOnVariableInScope() throws Exception {
     StarlarkThread thread = newThread();
     Module module =
         Module.withPredeclared(
             StarlarkSemantics.DEFAULT, /*predeclared=*/ ImmutableMap.of("a", "string"));

     assertThat(
             Starlark.execFile(
                 ParserInput.fromLines("a.startswith('str')"), FileOptions.DEFAULT, module, thread))
         .isEqualTo(true);
     Starlark.execFile(ParserInput.fromLines("a = 1"), FileOptions.DEFAULT, module, thread);
     assertThat(Starlark.execFile(ParserInput.fromLines("a"), FileOptions.DEFAULT, module, thread))
         .isEqualTo(1);
   }
 }
	// Copyright 2018 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;

	import static com.google.common.truth.Truth.assertThat;
	import static org.junit.Assert.assertThrows;

	import com.google.common.collect.ImmutableList;
	import com.google.common.collect.ImmutableMap;
	import com.google.devtools.build.lib.syntax.Debug.ReadyToPause;
	import com.google.devtools.build.lib.syntax.Debug.Stepping;
	import org.junit.Test;
	import org.junit.runner.RunWith;
	import org.junit.runners.JUnit4;

	/** Tests of debugging features of StarlarkThread. */
	@RunWith(JUnit4.class)
	public class StarlarkThreadDebuggingTest {

	// TODO(adonovan): rewrite these tests at a higher level.

	private static StarlarkThread newThread() {
	return new StarlarkThread(Mutability.create("test"), StarlarkSemantics.DEFAULT);
	}

	// Executes the definition of a trivial function f and returns the function value.
	private static StarlarkFunction defineFunc() throws Exception {
	return (StarlarkFunction)
	Starlark.execFile(
	ParserInput.fromLines("def f(): pass\nf"),
	FileOptions.DEFAULT,
	Module.create(),
	newThread());
	}

	@Test
	public void testListFramesEmptyStack() throws Exception {
	StarlarkThread thread = newThread();
	assertThat(Debug.getCallStack(thread)).isEmpty();
	assertThat(thread.getCallStack()).isEmpty();
	}

	@Test
	public void testListFramesFromBuiltin() throws Exception {
	// f is a built-in that captures the stack using the Debugger API.
	Object[] result = {null, null};
	StarlarkCallable f =
	new StarlarkCallable() {
	@Override
	public String getName() {
	return "f";
	}

	@Override
	public Object fastcall(StarlarkThread thread, Object[] positional, Object[] named) {
	result[0] = Debug.getCallStack(thread);
	result[1] = thread.getCallStack();
	return Starlark.NONE;
	}

	@Override
	public Location getLocation() {
	return Location.fromFileLineColumn("builtin", 12, 0);
	}

	@Override
	public String toString() {
	return "<debug function>";
	}
	};

	// Set up global environment.
	Module module =
	Module.withPredeclared(StarlarkSemantics.DEFAULT, ImmutableMap.of("a", 1, "b", 2, "f", f));

	// Execute a small file that calls f.
	ParserInput input =
	ParserInput.fromString(
	"def g(a, y, z):\n" // shadows global a
	+ " f()\n"
	+ "g(4, 5, 6)",
	"main.star");
	Starlark.execFile(input, FileOptions.DEFAULT, module, newThread());

	@SuppressWarnings("unchecked")
	ImmutableList<Debug.Frame> stack = (ImmutableList<Debug.Frame>) result[0];

	// Check the stack captured by f.
	// We compare printed string forms, as it gives more informative assertion failures.
	StringBuilder buf = new StringBuilder();
	for (Debug.Frame fr : stack) {
	buf.append(
	String.format(
	"%s @ %s local=%s\n", fr.getFunction().getName(), fr.getLocation(), fr.getLocals()));
	}
	assertThat(buf.toString())
	.isEqualTo(
	""
	// location is paren of g(4, 5, 6) call:
	+ "<toplevel> @ main.star:3:2 local={}\n"
	// location is paren of "f()" call:
	+ "g @ main.star:2:4 local={a=4, y=5, z=6}\n"
	// location is "current PC" in f.
	+ "f @ builtin:12 local={}\n");

	// Same, with "lite" stack API.
	assertThat(result[1].toString()) // an ImmutableList<StarlarkThread.CallStackEntry>
	.isEqualTo("[<toplevel>@main.star:3:2, g@main.star:2:4, f@builtin:12]");

	// TODO(adonovan): more tests:
	// - a stack containing functions defined in different modules.
	// - changing environment at various program points within a function.
	}

	@Test
	public void testStepIntoFunction() throws Exception {
	StarlarkThread thread = newThread();

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);
	thread.push(defineFunc());

	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepIntoFallsBackToStepOver() {
	// test that when stepping into, we'll fall back to stopping at the next statement in the
	// current frame
	StarlarkThread thread = newThread();

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);

	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepIntoFallsBackToStepOut() throws Exception {
	// test that when stepping into, we'll fall back to stopping when exiting the current frame
	StarlarkThread thread = newThread();
	thread.push(defineFunc());

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.INTO);
	thread.pop();

	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepOverFunction() throws Exception {
	StarlarkThread thread = newThread();

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.OVER);
	thread.push(defineFunc());

	assertThat(predicate.test(thread)).isFalse();
	thread.pop();
	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepOverFallsBackToStepOut() throws Exception {
	// test that when stepping over, we'll fall back to stopping when exiting the current frame
	StarlarkThread thread = newThread();
	thread.push(defineFunc());

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.OVER);
	thread.pop();

	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepOutOfInnerFrame() throws Exception {
	StarlarkThread thread = newThread();
	thread.push(defineFunc());

	ReadyToPause predicate = Debug.stepControl(thread, Stepping.OUT);

	assertThat(predicate.test(thread)).isFalse();
	thread.pop();
	assertThat(predicate.test(thread)).isTrue();
	}

	@Test
	public void testStepOutOfOutermostFrame() {
	StarlarkThread thread = newThread();

	assertThat(Debug.stepControl(thread, Stepping.OUT)).isNull();
	}

	@Test
	public void testStepControlWithNoSteppingReturnsNull() {
	StarlarkThread thread = newThread();

	assertThat(Debug.stepControl(thread, Stepping.NONE)).isNull();
	}

	@Test
	public void testEvaluateVariableInScope() throws Exception {
	Module module = Module.withPredeclared(StarlarkSemantics.DEFAULT, ImmutableMap.of("a", 1));

	StarlarkThread thread = newThread();
	Object a = Starlark.execFile(ParserInput.fromLines("a"), FileOptions.DEFAULT, module, thread);
	assertThat(a).isEqualTo(1);
	}

	@Test
	public void testEvaluateVariableNotInScopeFails() throws Exception {
	Module module = Module.create();

	SyntaxError.Exception e =
	assertThrows(
	SyntaxError.Exception.class,
	() ->
	Starlark.execFile(
	ParserInput.fromLines("b"), FileOptions.DEFAULT, module, newThread()));

	assertThat(e).hasMessageThat().isEqualTo("name 'b' is not defined");
	}

	@Test
	public void testEvaluateExpressionOnVariableInScope() throws Exception {
	StarlarkThread thread = newThread();
	Module module =
	Module.withPredeclared(
	StarlarkSemantics.DEFAULT, /predeclared=/ ImmutableMap.of("a", "string"));

	assertThat(
	Starlark.execFile(
	ParserInput.fromLines("a.startswith('str')"), FileOptions.DEFAULT, module, thread))
	.isEqualTo(true);
	Starlark.execFile(ParserInput.fromLines("a = 1"), FileOptions.DEFAULT, module, thread);
	assertThat(Starlark.execFile(ParserInput.fromLines("a"), FileOptions.DEFAULT, module, thread))
	.isEqualTo(1);
	}
	}