Bug 1869842 - Extend MockRegistry to support types and subkeys/children r=nrishel

Differential Revision: https://phabricator.services.mozilla.com/D199434

testing/modules/MockRegistry.sys.mjs

@@ -4,82 +4,232 @@
 
 import { MockRegistrar } from "resource://testing-common/MockRegistrar.sys.mjs";
 
+class MockWindowsRegKey {
+  key = null;
+
+  // --- Overridden nsISupports interface functions ---
+  QueryInterface = ChromeUtils.generateQI(["nsIWindowsRegKey"]);
+
+  #assertKey() {
+    if (this.key) {
+      return;
+    }
+    throw Components.Exception("invalid registry path", Cr.NS_ERROR_FAILURE);
+  }
+
+  #findOrMaybeCreateKey(root, path, mode, maybeCreateCallback) {
+    let rootKey = MockRegistry.getRoot(root);
+    let parts = path.split("\\");
+    if (parts.some(part => !part.length)) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+
+    let key = rootKey;
+    for (let part of parts) {
+      if (!key.subkeys.has(part)) {
+        maybeCreateCallback(key.subkeys, part);
+      }
+      key = key.subkeys.get(part);
+    }
+    this.key = key;
+  }
+
+  // --- Overridden nsIWindowsRegKey interface functions ---
+  open(root, path, mode) {
+    // eslint-disable-next-line no-unused-vars
+    this.#findOrMaybeCreateKey(root, path, mode, (subkeys, part) => {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    });
+  }
+
+  create(root, path, mode) {
+    this.#findOrMaybeCreateKey(root, path, mode, (subkeys, part) =>
+      subkeys.set(part, { subkeys: new Map(), values: new Map() })
+    );
+  }
+
+  close() {
+    this.key = null;
+  }
+
+  get valueCount() {
+    this.#assertKey();
+    return this.key.values.size;
+  }
+
+  hasValue(name) {
+    this.#assertKey();
+    return this.key.values.has(name);
+  }
+
+  #getValuePair(name, expectedType = null) {
+    this.#assertKey();
+    if (!this.key.values.has(name)) {
+      throw Components.Exception("invalid value name", Cr.NS_ERROR_FAILURE);
+    }
+    let [value, type] = this.key.values.get(name);
+    if (expectedType && type !== expectedType) {
+      throw Components.Exception("unexpected value type", Cr.NS_ERROR_FAILURE);
+    }
+    return [value, type];
+  }
+
+  getValueType(name) {
+    let [, type] = this.#getValuePair(name);
+    return type;
+  }
+
+  getValueName(index) {
+    if (!this.key || index >= this.key.values.size) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+    let names = Array.from(this.key.values.keys());
+    return names[index];
+  }
+
+  readStringValue(name) {
+    let [value] = this.#getValuePair(name, Ci.nsIWindowsRegKey.TYPE_STRING);
+    return value;
+  }
+
+  readIntValue(name) {
+    let [value] = this.#getValuePair(name, Ci.nsIWindowsRegKey.TYPE_INT);
+    return value;
+  }
+
+  readInt64Value(name) {
+    let [value] = this.#getValuePair(name, Ci.nsIWindowsRegKey.TYPE_INT64);
+    return value;
+  }
+
+  readBinaryValue(name) {
+    let [value] = this.#getValuePair(name, Ci.nsIWindowsRegKey.TYPE_BINARY);
+    return value;
+  }
+
+  #writeValuePair(name, value, type) {
+    this.#assertKey();
+    this.key.values.set(name, [value, type]);
+  }
+
+  writeStringValue(name, value) {
+    this.#writeValuePair(name, value, Ci.nsIWindowsRegKey.TYPE_STRING);
+  }
+
+  writeIntValue(name, value) {
+    this.#writeValuePair(name, value, Ci.nsIWindowsRegKey.TYPE_INT);
+  }
+
+  writeInt64Value(name, value) {
+    this.#writeValuePair(name, value, Ci.nsIWindowsRegKey.TYPE_INT64);
+  }
+
+  writeBinaryValue(name, value) {
+    this.#writeValuePair(name, value, Ci.nsIWindowsRegKey.TYPE_BINARY);
+  }
+
+  removeValue(name) {
+    this.#assertKey();
+    this.key.values.delete(name);
+  }
+
+  get childCount() {
+    this.#assertKey();
+    return this.key.subkeys.size;
+  }
+
+  getChildName(index) {
+    if (!this.key || index >= this.key.values.size) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+    let names = Array.from(this.key.subkeys.keys());
+    return names[index];
+  }
+
+  hasChild(name) {
+    this.#assertKey();
+    return this.key.subkeys.has(name);
+  }
+
+  removeChild(name) {
+    this.#assertKey();
+    let child = this.key.subkeys.get(name);
+
+    if (!child) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+    if (child.subkeys.size > 0) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+
+    this.key.subkeys.delete(name);
+  }
+
+  #findOrMaybeCreateChild(name, mode, maybeCreateCallback) {
+    this.#assertKey();
+    if (name.split("\\").length > 1) {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    }
+    if (!this.key.subkeys.has(name)) {
+      maybeCreateCallback(this.key.subkeys, name);
+    }
+    // This won't wrap in the same way as `Cc["@mozilla.org/windows-registry-key;1"].createInstance(nsIWindowsRegKey);`.
+    let subKey = new MockWindowsRegKey();
+    subKey.key = this.key.subkeys.get(name);
+    return subKey;
+  }
+
+  openChild(name, mode) {
+    // eslint-disable-next-line no-unused-vars
+    return this.#findOrMaybeCreateChild(name, mode, (subkeys, part) => {
+      throw Components.Exception("", Cr.NS_ERROR_FAILURE);
+    });
+  }
+
+  createChild(name, mode) {
+    return this.#findOrMaybeCreateChild(name, mode, (subkeys, part) =>
+      subkeys.set(part, { subkeys: new Map(), values: new Map() })
+    );
+  }
+}
+
 export class MockRegistry {
+  // All instances of `MockRegistry` share a single data-store; this is
+  // conceptually parallel to the Windows registry, which is a shared global
+  // resource.  It would be possible to have separate data-stores for separate
+  // instances with a little adjustment to `MockWindowsRegKey`.
+  //
+  // Top-level map is indexed by roots.  A "key" is an object that has
+  // `subkeys` and `values`, both maps indexed by strings.  Subkey items are
+  // again "key" objects.  Value items are `[value, type]` pairs.
+  //
+  // In pseudo-code:
+  //
+  // {Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER:
+  //  {subkeys:
+  //   {child: {subkeys: {}, values: {key: ["string_value", Ci.nsIWindowsRegKey.TYPE_STRING]}}},
+  //  values: {}
+  //  },
+  //  ...
+  // }
+  static roots;
+
   constructor() {
-    // Three level structure of Maps pointing to Maps pointing to Maps
+    MockRegistry.roots = new Map([
-    // this.roots is the top of the structure and has ROOT_KEY_* values
+      [
-    // as keys.  Maps at the second level are the values of the first
+        Ci.nsIWindowsRegKey.ROOT_KEY_LOCAL_MACHINE,
-    // level Map, they have registry keys (also called paths) as keys.
+        { subkeys: new Map(), values: new Map() },
-    // Third level maps are the values in second level maps, they have
+      ],
-    // map registry names to corresponding values (which in this implementation
+      [
-    // are always strings).
+        Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER,
-    this.roots = new Map([
+        { subkeys: new Map(), values: new Map() },
-      [Ci.nsIWindowsRegKey.ROOT_KEY_LOCAL_MACHINE, new Map()],
+      ],
-      [Ci.nsIWindowsRegKey.ROOT_KEY_CURRENT_USER, new Map()],
+      [
-      [Ci.nsIWindowsRegKey.ROOT_KEY_CLASSES_ROOT, new Map()],
+        Ci.nsIWindowsRegKey.ROOT_KEY_CLASSES_ROOT,
+        { subkeys: new Map(), values: new Map() },
+      ],
     ]);
 
-    let registry = this;
-
-    /**
-     * This is a mock nsIWindowsRegistry implementation. It only implements a
-     * subset of the interface used in tests.  In particular, only values
-     * of type string are supported.
-     */
-    function MockWindowsRegKey() {}
-    MockWindowsRegKey.prototype = {
-      values: null,
-
-      // --- Overridden nsISupports interface functions ---
-      QueryInterface: ChromeUtils.generateQI(["nsIWindowsRegKey"]),
-
-      // --- Overridden nsIWindowsRegKey interface functions ---
-      open(root, path) {
-        let rootKey = registry.getRoot(root);
-        if (!rootKey.has(path)) {
-          rootKey.set(path, new Map());
-        }
-        this.values = rootKey.get(path);
-      },
-
-      close() {
-        this.values = null;
-      },
-
-      get valueCount() {
-        if (!this.values) {
-          throw Components.Exception("", Cr.NS_ERROR_FAILURE);
-        }
-        return this.values.size;
-      },
-
-      hasValue(name) {
-        if (!this.values) {
-          return false;
-        }
-        return this.values.has(name);
-      },
-
-      getValueType() {
-        return Ci.nsIWindowsRegKey.TYPE_STRING;
-      },
-
-      getValueName(index) {
-        if (!this.values || index >= this.values.size) {
-          throw Components.Exception("", Cr.NS_ERROR_FAILURE);
-        }
-        let names = Array.from(this.values.keys());
-        return names[index];
-      },
-
-      readStringValue(name) {
-        if (!this.values) {
-          throw new Error("invalid registry path");
-        }
-        return this.values.get(name);
-      },
-    };
-
     // See bug 1688838 - nsNotifyAddrListener::CheckAdaptersAddresses might
     // attempt to use the registry off the main thread, so we disable that
     // feature while the mock registry is active.
@@ -100,7 +250,7 @@ export class MockRegistry {
 
     this.cid = MockRegistrar.register(
       "@mozilla.org/windows-registry-key;1",
-      MockWindowsRegKey
+      () => new MockWindowsRegKey()
     );
   }
 
@@ -121,7 +271,7 @@ export class MockRegistry {
     this.cid = null;
   }
 
-  getRoot(root) {
+  static getRoot(root) {
     if (!this.roots.has(root)) {
       throw new Error(`No such root ${root}`);
     }
@@ -129,17 +279,58 @@ export class MockRegistry {
   }
 
   setValue(root, path, name, value) {
-    let rootKey = this.getRoot(root);
+    let key = new MockWindowsRegKey();
-
+    key.create(root, path, Ci.nsIWindowsRegKey.ACCESS_ALL);
-    if (!rootKey.has(path)) {
-      rootKey.set(path, new Map());
-    }
-
-    let pathmap = rootKey.get(path);
     if (value == null) {
-      pathmap.delete(name);
+      try {
+        key.removeValue(name);
+      } catch (e) {
+        if (
+          !(e instanceof Ci.nsIException && e.result == Cr.NS_ERROR_FAILURE)
+        ) {
+          throw e;
+        }
+      }
     } else {
-      pathmap.set(name, value);
+      key.writeStringValue(name, value);
+    }
+  }
+
+  /**
+   * Dump given `key` (or, if not given, all roots), and all its value and its
+   * subkeys recursively, using the given function to `printOneLine`.
+   */
+  static dump(key = null, indent = "", printOneLine = console.log) {
+    let types = new Map([
+      [1, "REG_SZ"],
+      [3, "REG_BINARY"],
+      [4, "REG_DWORD"],
+      [11, "REG_QWORD"],
+    ]);
+
+    if (!key) {
+      let roots = [
+        "ROOT_KEY_LOCAL_MACHINE",
+        "ROOT_KEY_CURRENT_USER",
+        "ROOT_KEY_CLASSES_ROOT",
+      ];
+      for (let root of roots) {
+        printOneLine(indent + root);
+        this.dump(
+          this.roots.get(Ci.nsIWindowsRegKey[root]),
+          "  " + indent,
+          printOneLine
+        );
+      }
+    } else {
+      for (let [k, v] of key.values.entries()) {
+        let [value, type] = v;
+        printOneLine(`${indent}${k}: ${value} (${types.get(type)})`);
+      }
+      for (let [k, child] of key.subkeys.entries()) {
+        printOneLine(indent + k);
+        this.dump(child, "  " + indent, printOneLine);
+      }
     }
   }
 }

xpcom/tests/unit/test_windows_registry.js

@@ -5,10 +5,47 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+const { MockRegistry } = ChromeUtils.importESModule(
+  "resource://testing-common/MockRegistry.sys.mjs"
+);
+
 const nsIWindowsRegKey = Ci.nsIWindowsRegKey;
 let regKeyComponent = Cc["@mozilla.org/windows-registry-key;1"];
 
-function run_test() {
+// We run these tests twice: once against the native Windows registry, and a
+// second time against `MockRegistry`.  This gives some confidence that
+// `MockRegistry` implements the same APIs as the native Windows registry.
+
+// This order is important: the native registry test must run first, because
+// otherwise we would end up running the `MockRegistry` test twice without
+// checking it against the native Windows registry.
+
+add_task(function test_native_registry() {
+  info("Running test for native Windows registry");
+  run_one_test();
+});
+
+add_task(function test_MockRegistry() {
+  let registry = new MockRegistry();
+  registerCleanupFunction(() => {
+    registry.shutdown();
+  });
+
+  // Before, there's nothing -- just the 3 roots (HKLM, HKCU, HKCR).
+  let linesBefore = [];
+  MockRegistry.dump(null, "", linesBefore.push.bind(linesBefore));
+  strictEqual(linesBefore.length, 3);
+
+  info("Running test for MockRegistry");
+  run_one_test({ cleanup: false });
+
+  // After, there's something -- more than just the roots.
+  let linesAfter = [];
+  MockRegistry.dump(null, "", linesAfter.push.bind(linesAfter));
+  strictEqual(linesAfter.length, 8);
+});
+
+function run_one_test({ cleanup = true } = {}) {
   //* create a key structure in a spot that's normally writable (somewhere under HKCU).
   let testKey = regKeyComponent.createInstance(nsIWindowsRegKey);
 
@@ -28,11 +65,16 @@ function run_test() {
   //* check that the get* functions fail with the right exception codes if we ask for the wrong type or if the value name doesn't exist at all
   test_invalidread_functions(testKey);
 
+  //* check that removing/deleting values works
+  test_remove_functions(testKey);
+
   //* check that creating/enumerating/deleting child keys works
   test_childkey_functions(testKey);
 
   //* clean up
-  cleanup_test_run(testKey, keyName);
+  if (cleanup) {
+    cleanup_test_run(testKey, keyName);
+  }
 }
 
 function setup_test_run(testKey, keyName) {
@@ -152,6 +194,15 @@ function test_invalidread_functions(testKey) {
   }
 }
 
+function test_remove_functions(testKey) {
+  strictEqual(testKey.valueCount, 4);
+  testKey.removeValue(TESTDATA_INT64NAME);
+  strictEqual(testKey.valueCount, 3);
+
+  testKey.removeValue(TESTDATA_INT64NAME);
+  strictEqual(testKey.valueCount, 3);
+}
+
 function test_childkey_functions(testKey) {
   strictEqual(testKey.childCount, 0);
   strictEqual(testKey.hasChild(TESTDATA_CHILD_KEY), false);