Allow for unlimited data capture size

config.js

@@ -51,11 +51,12 @@ module.exports = {
     // gathered on large object. A value of 0 disables the limit.
     maxProperties: 0,
 
-    // Total 'size' if data to gather. This is NOT the number of bytes of data
+    // Total 'size' of data to gather. This is NOT the number of bytes of data
     // that are sent over the wire, but instead a very very coarse approximation
     // based on the length of names and values of the properties. This should
     // be somewhat proportional to the amount of processing needed to capture
-    // the data and subsequently the network traffic.
+    // the data and subsequently the network traffic. A value of 0 disables the
+    // limit.
     maxDataSize: 20000,
 
     // To limit the size of the buffer, we truncate long strings.

lib/state.js

@@ -145,8 +145,9 @@ StateResolver.prototype.capture_ = function() {
 
   // Now resolve the variables
   var index = MESSAGE_TABLE.length; // skip the sentinel values
+  var noLimit = that.config_.capture.maxDataSize === 0;
   while (index < that.rawVariableTable_.length && // NOTE: length changes in loop
-         that.totalSize_ < that.config_.capture.maxDataSize) {
+         (that.totalSize_ < that.config_.capture.maxDataSize || noLimit)) {
     assert(!that.resolvedVariableTable_[index]); // shouldn't have it resolved yet
     that.resolvedVariableTable_[index] =
       that.resolveMirror_(that.rawVariableTable_[index]);

test/standalone/test-max-data-size.js

@@ -0,0 +1,85 @@
+/*1* KEEP THIS CODE AT THE TOP TO AVOID LINE NUMBER CHANGES */
+/*2*/'use strict';
+/*3*/function foo(n) {
+/*4*/  var A = new Array(3); return n+42+A[0];
+/*5*/}
+/**
+ * Copyright 2015 Google Inc. 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.
+ */
+
+process.env.GCLOUD_DIAGNOSTICS_CONFIG = 'test/fixtures/test-config.js';
+
+var assert = require('assert');
+var logModule = require('@google/cloud-diagnostics-common').logger;
+var v8debugapi = require('../../lib/v8debugapi.js');
+var scanner = require('../../lib/scanner.js');
+var config = require('../../config.js');
+var api;
+
+var breakpointInFoo = {
+  id: 'fake-id-123',
+  location: { path: 'test-max-data-size.js', line: 4 }
+};
+
+describe('maxDataSize', function() {
+  before(function(done) {
+    if (!api) {
+      var logger = logModule.create(config.logLevel);
+      scanner.scan(true, config.workingDirectory, function(err, fileStats, hash) {
+        assert(!err);
+        api = v8debugapi.create(logger, config, fileStats);
+        done();
+      });
+    } else {
+      done();
+    }
+  });
+
+  it('should limit data reported', function(done) {
+    config.capture.maxDataSize = 5;
+    // clone a clean breakpointInFoo
+    var bp  = {id: breakpointInFoo.id, location: breakpointInFoo.location};
+    api.set(bp, function(err) {
+      assert.ifError(err);
+      api.wait(bp, function(err) {
+        assert.ifError(err);
+        assert(bp.variableTable.some(function(v) {
+          return v.status.description.format === 'Max data size reached';
+        }));
+        api.clear(bp);
+        done();
+      });
+      process.nextTick(function() {foo(2);});
+    });
+  });
+
+  it('should be unlimited if 0', function(done) {
+    config.capture.maxDataSize = 0;
+    // clone a clean breakpointInFoo
+    var bp  = {id: breakpointInFoo.id, location: breakpointInFoo.location};
+    api.set(bp, function(err) {
+      assert.ifError(err);
+      api.wait(bp, function(err) {
+        assert.ifError(err);
+        assert(bp.variableTable.reduce(function(acc, elem) {
+          return acc && elem.status.description.format !== 'Max data size reached';
+        }), true);
+        api.clear(bp);
+        done();
+      });
+      process.nextTick(function() {foo(2);});
+    });
+  });
+});