From 410badcbf47816f87a3fb85b06219cc8189b2bae Mon Sep 17 00:00:00 2001
From: Jason Fields <jfields@broadwaytechnology.com>
Date: Thu, 25 Jul 2019 10:21:12 -0400
Subject: [PATCH] Implement ampersand (&) action

This action repeats the last substitution, equivalent to `:s`.
Fixes #3808
---
 src/actions/commands/actions.ts  | 14 ++++++++++++++
 test/cmd_line/substitute.test.ts | 15 +++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/src/actions/commands/actions.ts b/src/actions/commands/actions.ts
index 95b5a7f59f1..0601bb5aee4 100644
--- a/src/actions/commands/actions.ts
+++ b/src/actions/commands/actions.ts
@@ -2153,6 +2153,20 @@ class CommandDot extends BaseCommand {
   }
 }
 
+@RegisterAction
+class CommandRepeatSubstitution extends BaseCommand {
+  modes = [ModeName.Normal];
+  keys = ['&'];
+
+  public async exec(position: Position, vimState: VimState): Promise<VimState> {
+    // Parsing the command from a string, while not ideal, is currently
+    // necessary to make this work with and without neovim integration
+    await commandLine.Run('s', vimState);
+
+    return vimState;
+  }
+}
+
 abstract class CommandFold extends BaseCommand {
   modes = [ModeName.Normal, ModeName.Visual, ModeName.VisualLine];
   commandName: string;
diff --git a/test/cmd_line/substitute.test.ts b/test/cmd_line/substitute.test.ts
index 97b520410d8..1f394859d58 100644
--- a/test/cmd_line/substitute.test.ts
+++ b/test/cmd_line/substitute.test.ts
@@ -333,6 +333,7 @@ suite('Basic substitute', () => {
       assertEqualLines(['bz']);
     });
   });
+
   suite('Substitute should use various previous search/substitute states', () => {
     test('Substitute with previous search using *', async () => {
       await modeHandler.handleMultipleKeyEvents([
@@ -364,6 +365,7 @@ suite('Basic substitute', () => {
 
       assertEqualLines(['fighters', 'bar', 'fighters', 'bar']);
     });
+
     test('Substitute with previous search using #', async () => {
       await modeHandler.handleMultipleKeyEvents([
         'i',
@@ -392,6 +394,7 @@ suite('Basic substitute', () => {
 
       assertEqualLines(['foo', 'fighters', 'foo', 'fighters']);
     });
+
     test('Substitute with previous search using /', async () => {
       await modeHandler.handleMultipleKeyEvents([
         'i',
@@ -424,6 +427,7 @@ suite('Basic substitute', () => {
 
       assertEqualLines(['fighters', 'bar', 'fighters', 'bar']);
     });
+
     newTest({
       title: 'Substitute with parameters should update search state',
       start: ['foo', 'bar', 'foo', 'bar|'],
@@ -434,6 +438,7 @@ suite('Basic substitute', () => {
         'rr', // and replace a with r
       end: ['foo', 'bite', 'foo', 'b|rr'],
     });
+
     newTest({
       title:
         'Substitute with empty replacement should delete previous substitution (all variants) and accepts flags',
@@ -474,6 +479,7 @@ suite('Basic substitute', () => {
         '|  is here',
       ],
     });
+
     newTest({
       title:
         'Substitute with no pattern should repeat previous substitution and not alter search state',
@@ -486,12 +492,14 @@ suite('Basic substitute', () => {
         'rp', // and replace l with p (confirming search state was unaltered)
       end: ['legend', 'zelda', 'legend', 'zelda', '|pink'],
     });
+
     newTest({
       title: 'Substitute repeat previous should accept flags',
       start: ['|fooo'],
       keysPressed: ':s/o/un\n:s g\n', // repeated replacement accepts g flag, replacing all other occurrences
       end: ['|fununun'],
     });
+
     test('Substitute with empty search string should use last searched pattern', async () => {
       await modeHandler.handleMultipleKeyEvents([
         'i',
@@ -528,5 +536,12 @@ suite('Basic substitute', () => {
 
       assertEqualLines(['foo', 'fighters', 'foo', 'fighters']);
     });
+
+    newTest({
+      title: 'Ampersand (&) should repeat the last substitution',
+      start: ['|foo bar baz'],
+      keysPressed: ':s/ba/t\n' + '&',
+      end: ['|foo tr tz'],
+    });
   });
 });