[inspector] restore provisional breakpoints smarter

test/inspector/debugger/restore-breakpoint.js

Index: test/inspector/debugger/restore-breakpoint.js
diff --git a/test/inspector/debugger/restore-breakpoint.js b/test/inspector/debugger/restore-breakpoint.js
new file mode 100644
index 0000000000000000000000000000000000000000..19ca98d387f2c2ee870ca62247af8c322c269b09
--- /dev/null
+++ b/test/inspector/debugger/restore-breakpoint.js
@@ -0,0 +1,68 @@
+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+print('Checks that debugger agent uses source content to restore breakpoints.');
+
+Protocol.Debugger.enable();
+InspectorTest.runTestSuite([
+  function testSameSource(next) {
+    var source = 'function foo() {\nboo();\n}';
+    test(source, source, { lineNumber: 1, columnNumber: 0 }, next);
+  },
+
+  function testOneLineOffset(next) {
+    var source = 'function foo() {\nboo();\n}';
+    var newSource = 'function foo() {\nboo();\nboo();\n}';
+    test(source, newSource, { lineNumber: 1, columnNumber: 0 }, next);
+  },
+
+  function testTwoSimilarLinesCloseToOriginalLocation1(next) {
+    var source = 'function foo() {\n\n\nboo();\n}';
+    var newSource = 'function foo() {\nboo();\n\nnewCode();\nboo();\n\n\n\nboo();\n}';
+    test(source, newSource, { lineNumber: 3, columnNumber: 0 }, next);
+  },
+
+  function testTwoSimilarLinesCloseToOriginalLocation2(next) {
+    var source = 'function foo() {\n\n\nboo();\n}';
+    var newSource = 'function foo() {\nboo();\nnewLongCode();\nnewCode();\nboo();\n\n\n\nboo();\n}';
+    test(source, newSource, { lineNumber: 3, columnNumber: 0 }, next);
+  },
+
+  function testHintIgnoreWhiteSpaces(next) {
+    var source = 'function foo() {\n\n\n\nboo();\n}';
+    var newSource = 'function foo() {\nfoo();\n\n\nboo();\n}';
+    test(source, newSource, { lineNumber: 1, columnNumber: 0 }, next);
+  },
+
+  function testCheckOnlyLimitedOffsets(next) {
+    var source = 'function foo() {\nboo();\n}';
+    var longString = Array(1000).join(';');
+    var newSource = `function foo() {\nnewCode();\n${longString};\nboo();\n}`;
+    test(source, newSource, { lineNumber: 1, columnNumber: 0 }, next);
+  }
+]);
+
+var finishedTests = 0;
+function test(source, newSource, location, next) {
+  var sourceURL = `test${++finishedTests}.js`;
+  Protocol.Debugger.setBreakpointByUrl({
+    url: sourceURL,
+    lineNumber: location.lineNumber,
+    columnNumber: location.columnNumber
+  }).then(() => Protocol.Runtime.evaluate({ expression: `${source}\n//# sourceURL=${sourceURL}` }))
+    .then(() => Protocol.Runtime.evaluate({ expression: `${newSource}\n//# sourceURL=${sourceURL}` }))
+    .then(next);
+
+  var firstBreakpoint = true;
+  Protocol.Debugger.onBreakpointResolved(message => {
+    var lineNumber = message.params.location.lineNumber;
+    var columnNumber = message.params.location.columnNumber;
+    var currentSource = firstBreakpoint ? source : newSource;
+    var lines = currentSource.split('\n');
+    lines = lines.map(line => line.substring(0, 77) + (line.length > 77 ? '...' : ''));
+    lines[lineNumber] = lines[lineNumber].slice(0, columnNumber) + '#' + lines[lineNumber].slice(columnNumber);
+    InspectorTest.log(lines.join('\n'));
+    firstBreakpoint = false;
+  });
+}