1 files changed, 110 insertions, 0 deletions
diff --git a/devtools/server/actors/common.js b/devtools/server/actors/common.js
new file mode 100644
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+++ b/devtools/server/actors/common.js
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+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/. */
+
+"use strict";
+
+class SourceLocation {
+  /**
+   * A SourceLocation represents a location in a source.
+   *
+   * @param SourceActor actor
+   *        A SourceActor representing a source.
+   * @param Number line
+   *        A line within the given source.
+   * @param Number column
+   *        A column within the given line.
+   */
+  constructor(actor, line, column) {
+    this._connection = actor ? actor.conn : null;
+    this._actorID = actor ? actor.actorID : undefined;
+    this._line = line;
+    this._column = column;
+  }
+
+  get sourceActor() {
+    return this._connection ? this._connection.getActor(this._actorID) : null;
+  }
+
+  get url() {
+    return this.sourceActor.url;
+  }
+
+  get line() {
+    return this._line;
+  }
+
+  get column() {
+    return this._column;
+  }
+
+  get sourceUrl() {
+    return this.sourceActor.url;
+  }
+
+  equals(other) {
+    return (
+      this.sourceActor.url == other.sourceActor.url &&
+      this.line === other.line &&
+      (this.column === undefined ||
+        other.column === undefined ||
+        this.column === other.column)
+    );
+  }
+
+  toJSON() {
+    return {
+      source: this.sourceActor.form(),
+      line: this.line,
+      column: this.column,
+    };
+  }
+}
+
+exports.SourceLocation = SourceLocation;
+
+/**
+ * A method decorator that ensures the actor is in the expected state before
+ * proceeding. If the actor is not in the expected state, the decorated method
+ * returns a rejected promise.
+ *
+ * The actor's state must be at this.state property.
+ *
+ * @param String expectedState
+ *        The expected state.
+ * @param String activity
+ *        Additional info about what's going on.
+ * @param Function methodFunc
+ *        The actor method to proceed with when the actor is in the expected
+ *        state.
+ *
+ * @returns Function
+ *          The decorated method.
+ */
+function expectState(expectedState, methodFunc, activity) {
+  return function (...args) {
+    if (this.state !== expectedState) {
+      const msg =
+        `Wrong state while ${activity}:` +
+        `Expected '${expectedState}', ` +
+        `but current state is '${this.state}'.`;
+      return Promise.reject(new Error(msg));
+    }
+
+    return methodFunc.apply(this, args);
+  };
+}
+
+exports.expectState = expectState;
+
+/**
+ * Autobind method from a `bridge` property set on some actors where the
+ * implementation is delegated to a separate class, and where `bridge` points
+ * to an instance of this class.
+ */
+function actorBridgeWithSpec(methodName) {
+  return function () {
+    return this.bridge[methodName].apply(this.bridge, arguments);
+  };
+}
+exports.actorBridgeWithSpec = actorBridgeWithSpec;