Implement Ctrl+G and :file (VSCodeVim#3723)

These both show the file name, line count, and relative position in the status bar.
Fixes VSCodeVim#3700

package.json

@@ -178,6 +178,11 @@
         "command": "extension.vim_ctrl+f",
         "when": "editorTextFocus && vim.active && vim.use<C-f> && vim.mode != 'Insert' && !inDebugRepl"
       },
+      {
+        "key": "ctrl+g",
+        "command": "extension.vim_ctrl+g",
+        "when": "editorTextFocus && vim.active && vim.use<C-g> && !inDebugRepl"
+      },
       {
         "key": "ctrl+h",
         "command": "extension.vim_ctrl+h",

src/actions/commands/actions.ts

@@ -24,7 +24,7 @@ import { BaseAction } from './../base';
 import { commandLine } from './../../cmd_line/commandLine';
 import * as operator from './../operator';
 import { Jump } from '../../jumps/jump';
-import { ReportLinesChanged, ReportClear } from '../../util/statusBarTextUtils';
+import { ReportLinesChanged, ReportClear, ReportFileInfo } from '../../util/statusBarTextUtils';
 
 export class DocumentContentChangeAction extends BaseAction {
   contentChanges: {
@@ -690,7 +690,10 @@ class CommandMoveHalfPageDown extends CommandEditorScroll {
       if (newPositionLine > maxLineValue) {
         newPosition = new Position(0, 0).getDocumentEnd();
       } else {
-        const newPositionColumn = Math.min(startColumn, TextEditor.getLineMaxColumn(newPositionLine));
+        const newPositionColumn = Math.min(
+          startColumn,
+          TextEditor.getLineMaxColumn(newPositionLine)
+        );
         newPosition = new Position(newPositionLine, newPositionColumn);
       }
     }
@@ -4266,3 +4269,19 @@ class ActionOverrideCmdAltUp extends BaseCommand {
     return vimState;
   }
 }
+
+@RegisterAction
+class ActionShowFileInfo extends BaseCommand {
+  modes = [ModeName.Normal];
+  keys = [['<C-g>']];
+
+  runsOnceForEveryCursor() {
+    return false;
+  }
+
+  public async exec(position: Position, vimState: VimState): Promise<VimState> {
+    ReportFileInfo(position, vimState);
+
+    return vimState;
+  }
+}

src/cmd_line/commands/fileInfo.ts

@@ -0,0 +1,9 @@
+import { CommandBase } from "../node";
+import { VimState } from "../../state/vimState";
+import { ReportFileInfo } from "../../util/statusBarTextUtils";
+
+export class FileInfoCommand extends CommandBase {
+  async execute(vimState: VimState): Promise<void> {
+    ReportFileInfo(vimState.cursors[0].start, vimState);
+  }
+}

src/cmd_line/subparser.ts

@@ -15,6 +15,7 @@ import { parseWallCommandArgs } from './subparsers/wall';
 import { parseWriteCommandArgs } from './subparsers/write';
 import { parseWriteQuitCommandArgs } from './subparsers/writequit';
 import { parseWriteQuitAllCommandArgs } from './subparsers/writequitall';
+import { parseFileInfoCommandArgs } from './subparsers/fileInfo';
 
 // maps command names to parsers for said commands.
 export const commandParsers = {
@@ -108,4 +109,9 @@ export const commandParsers = {
   d: parseDeleteRangeLinesCommandArgs,
 
   sort: parseSortCommandArgs,
+
+  f: parseFileInfoCommandArgs,
+  fi: parseFileInfoCommandArgs,
+  fil: parseFileInfoCommandArgs,
+  file: parseFileInfoCommandArgs,
 };

src/cmd_line/subparsers/fileInfo.ts

@@ -0,0 +1,6 @@
+import { FileInfoCommand } from "../commands/fileInfo";
+
+export function parseFileInfoCommandArgs(args: string): FileInfoCommand {
+  // TODO: implement bang, file name parameters. http://vimdoc.sourceforge.net/htmldoc/editing.html#CTRL-G
+  return new FileInfoCommand();
+}

src/util/statusBarTextUtils.ts

@@ -2,6 +2,7 @@ import { ModeName } from '../mode/mode';
 import { StatusBar } from '../statusBar';
 import { VimState } from '../state/vimState';
 import { configuration } from '../configuration/configuration';
+import { Position } from '../common/motion/position';
 
 export function ReportClear(vimState: VimState) {
   StatusBar.Set('', vimState.currentMode, vimState.isRecordingMacro, true);
@@ -48,3 +49,19 @@ export function ReportLinesYanked(numLinesYanked: number, vimState: VimState) {
     ReportClear(vimState);
   }
 }
+
+/**
+ * Shows the active file's path and line count as well as position in the file as a percentage.
+ * Triggered via `ctrl-g` or `:file`.
+ */
+export function ReportFileInfo(position: Position, vimState: VimState) {
+  const doc = vimState.editor.document;
+  const progress = Math.floor(((position.line + 1) / doc.lineCount) * 100);
+
+  StatusBar.Set(
+    `"${doc.fileName}" ${doc.lineCount} lines --${progress}%--`,
+    vimState.currentMode,
+    vimState.isRecordingMacro,
+    true
+  );
+}