From 4c4f8850efcc1637b5a640796ca6d03b882f81c8 Mon Sep 17 00:00:00 2001
From: xconverge <sevendaystillsean@gmail.com>
Date: Wed, 8 Mar 2017 22:03:12 -0800
Subject: [PATCH] fixes #1373

---
 src/cmd_line/commands/substitute.ts | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/cmd_line/commands/substitute.ts b/src/cmd_line/commands/substitute.ts
index 508f1fa1452..12dd91d800d 100644
--- a/src/cmd_line/commands/substitute.ts
+++ b/src/cmd_line/commands/substitute.ts
@@ -59,7 +59,7 @@ export class SubstituteCommand extends node.CommandBase {
     return this._arguments;
   }
 
-  getRegex(args: ISubstituteCommandArguments) {
+  getRegex(args: ISubstituteCommandArguments, modeHandler: ModeHandler) {
     let jsRegexFlags = "";
 
     if (args.flags & SubstituteFlags.ReplaceAll) {
@@ -70,6 +70,15 @@ export class SubstituteCommand extends node.CommandBase {
       jsRegexFlags += "i";
     }
 
+    // If no pattern is entered, use previous search state
+    if (args.pattern === "") {
+      const prevSearchState = modeHandler.vimState.globalState.searchStatePrevious;
+      if (prevSearchState) {
+        const prevSearchString = prevSearchState[prevSearchState.length - 1].searchString;
+        args.pattern = prevSearchString;
+      }
+    }
+
     return new RegExp(args.pattern, jsRegexFlags);
   }
 
@@ -82,8 +91,8 @@ export class SubstituteCommand extends node.CommandBase {
     }
   }
 
-  async execute(): Promise<void> {
-    const regex = this.getRegex(this._arguments);
+  async execute(modeHandler : ModeHandler): Promise<void> {
+    const regex = this.getRegex(this._arguments, modeHandler);
     const selection = vscode.window.activeTextEditor.selection;
     const line = selection.start.isBefore(selection.end) ? selection.start.line : selection.end.line;
 
@@ -110,7 +119,7 @@ export class SubstituteCommand extends node.CommandBase {
     // TODO: Global Setting.
     // TODO: There are differencies between Vim Regex and JS Regex.
 
-    let regex = this.getRegex(this._arguments);
+    let regex = this.getRegex(this._arguments, modeHandler);
     for (let currentLine = startLine.line; currentLine <= endLine.line && currentLine < TextEditor.getLineCount(); currentLine++) {
       await this.replaceTextAtLine(currentLine, regex);
     }