Clear problems view when a database is removed

This commit fixes the problem whereby a database is removed and the
problems associated with queries run from that database stick around
in the problems view.

Also, once problems are cleared, we need to make sure that we uncheck
the checkbox in the results view.

This commit has several limitations:

1. There is duplicated code for message handling in both results.tsx and
result-tables.tsx.
2. Problems are cleared whenever there is *any* change to any database.
Ideally we should only clear problems when a database is removed and
only problems associated with that database. I'll fix part of this in
a future commit.

Resolves #525

extensions/ql-vscode/src/interface-types.ts

@@ -127,11 +127,16 @@ export interface NavigatePathMsg {
   direction: number;
 }
 
+export interface UntoggleShowProblemsMsg {
+  t: 'untoggleShowProblems';
+}
+
 export type IntoResultsViewMsg =
   | ResultsUpdatingMsg
   | SetStateMsg
   | ShowInterpretedPageMsg
-  | NavigatePathMsg;
+  | NavigatePathMsg
+  | UntoggleShowProblemsMsg;
 
 export type FromResultsViewMsg =
   | ViewSourceFileMsg

extensions/ql-vscode/src/interface.ts

@@ -132,6 +132,17 @@ export class InterfaceManager extends DisposableObject {
         this.navigatePathStep.bind(this, -1)
       )
     );
+
+    this.push(
+      this.databaseManager.onDidChangeDatabaseItem(() => {
+        // Consider only clearing database items when a database
+        // is removed and only clearing items from that database.
+        this._diagnosticCollection.clear();
+        this.postMessage({
+          t: 'untoggleShowProblems'
+        });
+      })
+    );
   }
 
   navigatePathStep(direction: number): void {

extensions/ql-vscode/src/view/result-tables.tsx

@@ -11,7 +11,8 @@ import {
   ALERTS_TABLE_NAME,
   SELECT_TABLE_NAME,
   getDefaultResultSetName,
-  ParsedResultSets
+  ParsedResultSets,
+  IntoResultsViewMsg
 } from '../interface-types';
 import { PathTable } from './alert-table';
 import { RawTable } from './raw-results-table';
@@ -41,6 +42,7 @@ export interface ResultTablesProps {
 interface ResultTablesState {
   selectedTable: string; // name of selected result set
   selectedPage: string; // stringified selected page
+  problemsViewSelected: boolean;
 }
 
 const UPDATING_RESULTS_TEXT_CLASS_NAME = 'vscode-codeql__result-tables-updating-text';
@@ -101,7 +103,17 @@ export class ResultTables
     super(props);
     const selectedTable = props.parsedResultSets.selectedTable || getDefaultResultSet(this.getResultSets());
     const selectedPage = (props.parsedResultSets.pageNumber + 1) + '';
-    this.state = { selectedTable, selectedPage };
+    this.state = {
+      selectedTable,
+      selectedPage,
+      problemsViewSelected: false
+    };
+  }
+
+  untoggleProbemsView() {
+    this.setState({
+      problemsViewSelected: false
+    });
   }
 
   private onTableSelectionChange = (event: React.ChangeEvent<HTMLSelectElement>): void => {
@@ -115,26 +127,39 @@ export class ResultTables
 
   private alertTableExtras(): JSX.Element | undefined {
     const { database, resultsPath, metadata, origResultsPaths } = this.props;
+    const handleCheckboxChanged = (e: React.ChangeEvent<HTMLInputElement>) => {
+      if (e.target.checked === this.state.problemsViewSelected) {
+        // no change
+        return;
+      }
+      this.setState({
+        problemsViewSelected: e.target.checked
+      });
+      if (resultsPath !== undefined) {
+        vscode.postMessage({
+          t: 'toggleDiagnostics',
+          origResultsPaths: origResultsPaths,
+          databaseUri: database.databaseUri,
+          visible: e.target.checked,
+          metadata: metadata
+        });
+      }
+    };
 
-    const displayProblemsAsAlertsToggle =
-      <div className={toggleDiagnosticsClassName}>
-        <input type="checkbox" id="toggle-diagnostics" name="toggle-diagnostics" onChange={(e) => {
-          if (resultsPath !== undefined) {
-            vscode.postMessage({
-              t: 'toggleDiagnostics',
-              origResultsPaths: origResultsPaths,
-              databaseUri: database.databaseUri,
-              visible: e.target.checked,
-              metadata: metadata
-            });
-          }
-        }} />
-        <label htmlFor="toggle-diagnostics">Show results in Problems view</label>
-      </div>;
-
-    return <div className={alertExtrasClassName}>
-      {displayProblemsAsAlertsToggle}
-    </div>;
+    return (
+      <div className={alertExtrasClassName}>
+        <div className={toggleDiagnosticsClassName}>
+          <input
+            type="checkbox"
+            id="toggle-diagnostics"
+            name="toggle-diagnostics"
+            onChange={handleCheckboxChanged}
+            checked={this.state.problemsViewSelected}
+          />
+          <label htmlFor="toggle-diagnostics">Show results in Problems view</label>
+        </div>
+      </div>
+    );
   }
 
   getOffset(): number {
@@ -244,6 +269,40 @@ export class ResultTables
       }
     </div>;
   }
+
+  handleMessage(msg: IntoResultsViewMsg): void {
+    switch (msg.t) {
+      case 'untoggleShowProblems':
+        this.setState({
+          problemsViewSelected: false
+        });
+        break;
+
+      default:
+        // noop
+    }
+  }
+
+  // TODO: Duplicated from results.tsx consider a way to
+  // avoid this duplication
+  componentDidMount(): void {
+    this.vscodeMessageHandler = (evt) =>
+      evt.origin === window.origin
+        ? this.handleMessage(evt.data as IntoResultsViewMsg)
+        : console.error(`Invalid event origin ${evt.origin}`);
+
+    window.addEventListener('message', this.vscodeMessageHandler);
+  }
+
+  componentWillUnmount(): void {
+    if (this.vscodeMessageHandler) {
+      window.removeEventListener('message', this.vscodeMessageHandler);
+    }
+  }
+
+  private vscodeMessageHandler:
+    | ((ev: MessageEvent) => void)
+    | undefined = undefined;
 }
 
 class ResultTable extends React.Component<ResultTableProps, {}> {

extensions/ql-vscode/src/view/results.tsx

@@ -137,6 +137,11 @@ class App extends React.Component<{}, ResultsViewState> {
       case 'navigatePath':
         onNavigation.fire(msg);
         break;
+
+      case 'untoggleShowProblems':
+        // noop
+        break;
+
       default:
         assertNever(msg);
     }