From 64e6c8d6c1848f55dc686639926d964d3a21b2ca Mon Sep 17 00:00:00 2001
From: mattirn <matti.rintanikkola@gmail.com>
Date: Fri, 15 Feb 2019 16:05:25 +0100
Subject: [PATCH] Widgets: accept-and-infer-next-history, accept-and-hold &
 accept-line-and-down-history

refactoring...

widgets: accept-and-infer-next-history & accept-and-hold

manage acceptAndHold() when buffer is empty.
---
 .../java/org/jline/reader/LineReader.java     |  3 +
 .../org/jline/reader/impl/LineReaderImpl.java | 57 +++++++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/reader/src/main/java/org/jline/reader/LineReader.java b/reader/src/main/java/org/jline/reader/LineReader.java
index b6e50da33..7c32998c4 100644
--- a/reader/src/main/java/org/jline/reader/LineReader.java
+++ b/reader/src/main/java/org/jline/reader/LineReader.java
@@ -95,7 +95,10 @@ public interface LineReader {
     String CALLBACK_FINISH = "callback-finish";
     String CALLBACK_KEYMAP = "callback-keymap";
 
+    String ACCEPT_AND_INFER_NEXT_HISTORY = "accept-and-infer-next-history";
+    String ACCEPT_AND_HOLD = "accept-and-hold";
     String ACCEPT_LINE = "accept-line";
+    String ACCEPT_LINE_AND_DOWN_HISTORY = "accept-line-and-down-history";
     String ARGUMENT_BASE = "argument-base";
     String BACKWARD_CHAR = "backward-char";
     String BACKWARD_DELETE_CHAR = "backward-delete-char";
diff --git a/reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java b/reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java
index 3739a083f..06dbd13a5 100644
--- a/reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java
+++ b/reader/src/main/java/org/jline/reader/impl/LineReaderImpl.java
@@ -241,6 +241,11 @@ protected enum BellType {
 
     protected int smallTerminalOffset = 0;
 
+    /*
+     * accept-and-infer-next-history, accept-and-hold & accept-line-and-down-history
+     */
+    protected boolean nextCommandFromHistory = false;
+    protected int nextHistoryId = -1;
 
 
     public LineReaderImpl(Terminal terminal) throws IOException {
@@ -497,6 +502,17 @@ public String readLine(String prompt, String rightPrompt, MaskingCallback maskin
             if (buffer != null) {
                 buf.write(buffer);
             }
+            if (nextCommandFromHistory && nextHistoryId > 0) {
+                if (history.size() > nextHistoryId) {
+                    history.moveTo(nextHistoryId);
+                } else {
+                    history.moveTo(history.last());
+                }
+                buf.write(history.current());
+            } else {
+                nextHistoryId = -1;
+            }
+            nextCommandFromHistory = false;
             undo.clear();
             parsedLine = null;
             keyMap = MAIN;
@@ -2712,6 +2728,42 @@ protected boolean quit() {
         return acceptLine();
     }
 
+    protected boolean acceptAndHold() {
+        nextCommandFromHistory = false;
+        acceptLine();
+        if (!buf.toString().isEmpty()) {
+            nextHistoryId = Integer.MAX_VALUE;
+            nextCommandFromHistory = true;
+        }
+        return nextCommandFromHistory;
+    }
+
+    protected boolean acceptLineAndDownHistory() {
+        nextCommandFromHistory = false;
+        acceptLine();
+        if (nextHistoryId < 0) {
+            nextHistoryId = history.index();
+        }
+        if (history.size() > nextHistoryId + 1) {
+            nextHistoryId++;
+            nextCommandFromHistory = true;
+        }
+        return nextCommandFromHistory;
+    }
+    
+    protected boolean acceptAndInferNextHistory() {
+        nextCommandFromHistory = false;
+        acceptLine();
+        if (!buf.toString().isEmpty()) {
+            nextHistoryId = searchBackwards(buf.toString(), history.last());
+            if (nextHistoryId >= 0 && history.size() > nextHistoryId + 1) {
+                nextHistoryId++;
+                nextCommandFromHistory = true;            
+            }
+        }
+        return nextCommandFromHistory;
+    }
+
     protected boolean acceptLine() {
         parsedLine = null;
         if (!isSet(Option.DISABLE_EVENT_EXPANSION)) {
@@ -3345,7 +3397,10 @@ protected boolean whatCursorPosition() {
 
     protected Map<String, Widget> builtinWidgets() {
         Map<String, Widget> widgets = new HashMap<>();
+        addBuiltinWidget(widgets, ACCEPT_AND_INFER_NEXT_HISTORY, this::acceptAndInferNextHistory);
+        addBuiltinWidget(widgets, ACCEPT_AND_HOLD, this::acceptAndHold);
         addBuiltinWidget(widgets, ACCEPT_LINE, this::acceptLine);
+        addBuiltinWidget(widgets, ACCEPT_LINE_AND_DOWN_HISTORY, this::acceptLineAndDownHistory);
         addBuiltinWidget(widgets, ARGUMENT_BASE, this::argumentBase);
         addBuiltinWidget(widgets, BACKWARD_CHAR, this::backwardChar);
         addBuiltinWidget(widgets, BACKWARD_DELETE_CHAR, this::backwardDeleteChar);
@@ -5399,6 +5454,7 @@ public KeyMap<Binding> emacs() {
         bind(emacs, CLEAR_SCREEN,                           ctrl('L'));
         bind(emacs, ACCEPT_LINE,                            ctrl('M'));
         bind(emacs, DOWN_LINE_OR_HISTORY,                   ctrl('N'));
+        bind(emacs, ACCEPT_LINE_AND_DOWN_HISTORY,           ctrl('O'));
         bind(emacs, UP_LINE_OR_HISTORY,                     ctrl('P'));
         bind(emacs, HISTORY_INCREMENTAL_SEARCH_BACKWARD,    ctrl('R'));
         bind(emacs, HISTORY_INCREMENTAL_SEARCH_FORWARD,     ctrl('S'));
@@ -5442,6 +5498,7 @@ public KeyMap<Binding> emacs() {
         bind(emacs, END_OF_HISTORY,                         alt('>'));
         bind(emacs, LIST_CHOICES,                           alt('?'));
         bind(emacs, DO_LOWERCASE_VERSION,                   range("^[A-^[Z"));
+        bind(emacs, ACCEPT_AND_HOLD,                        alt('a'));
         bind(emacs, BACKWARD_WORD,                          alt('b'));
         bind(emacs, CAPITALIZE_WORD,                        alt('c'));
         bind(emacs, KILL_WORD,                              alt('d'));