readline,repl: improve history up/previous

Reaching the history end caused the last entry to be persistent. That way there's no actualy feedback to the user that the history end is reached. Instead, visualize the original input line and keep the history index at the history end in case the user wants to go back again.
nodejs · BridgeAR · Dec 26, 2019 · Dec 27, 2019 · Dec 27, 2019 · Dec 29, 2019
commit 5a213fe47083b543a803242a51d8da013601918f
diff --git a/lib/readline.js b/lib/readline.js
@@ -718,7 +718,7 @@ Interface.prototype._historyNext = function() {
 };
 
 Interface.prototype._historyPrev = function() {
-  if (this.historyIndex < this.history.length) {
+  if (this.historyIndex < this.history.length && this.history.length) {
     const search = this[kSubstringSearch] || '';
     let index = this.historyIndex + 1;
     while (index < this.history.length &&
@@ -727,9 +727,7 @@ Interface.prototype._historyPrev = function() {
       index++;
     }
     if (index === this.history.length) {
-      // TODO(BridgeAR): Change this to:
-      // this.line = search;
-      return;
+      this.line = search;
     } else {
       this.line = this.history[index];
     }

diff --git a/test/parallel/test-readline-interface.js b/test/parallel/test-readline-interface.js
@@ -482,12 +482,20 @@ function isWarned(emitter) {
     fi.emit('keypress', '.', { name: 'up' }); // 'baz'
     assert.strictEqual(rli.historyIndex, 2);
     assert.strictEqual(rli.line, 'baz');
-    fi.emit('keypress', '.', { name: 'up' }); // 'baz'
-    assert.strictEqual(rli.historyIndex, 2);
-    assert.strictEqual(rli.line, 'baz');
-    fi.emit('keypress', '.', { name: 'up' }); // 'baz'
-    assert.strictEqual(rli.historyIndex, 2);
-    assert.strictEqual(rli.line, 'baz');
+    fi.emit('keypress', '.', { name: 'up' }); // 'ba'
+    assert.strictEqual(rli.historyIndex, 4);
+    assert.strictEqual(rli.line, 'ba');
+    fi.emit('keypress', '.', { name: 'up' }); // 'ba'
+    assert.strictEqual(rli.historyIndex, 4);
+    assert.strictEqual(rli.line, 'ba');
+    // Deactivate substring history search and reset history index.
+    fi.emit('keypress', '.', { name: 'right' }); // 'ba'
+    assert.strictEqual(rli.historyIndex, -1);
+    assert.strictEqual(rli.line, 'ba');
+    // Substring history search activated.
+    fi.emit('keypress', '.', { name: 'up' }); // 'ba'
+    assert.strictEqual(rli.historyIndex, 0);
+    assert.strictEqual(rli.line, 'bat');
     rli.close();
   }
 

diff --git a/test/parallel/test-repl-history-navigation.js b/test/parallel/test-repl-history-navigation.js
@@ -78,8 +78,7 @@ const tests = [
   },
   {
     env: { NODE_REPL_HISTORY: defaultHistoryPath },
-    checkTotal: true,
-    test: [UP, UP, UP, UP, UP, DOWN, DOWN, DOWN, DOWN],
+    test: [UP, UP, UP, UP, UP, DOWN, DOWN, DOWN, DOWN, DOWN],
     expected: [prompt,
                `${prompt}Array(100).fill(1).map((e, i) => i ** 2)`,
                prev && '\n// [ 0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, ' +
@@ -92,6 +91,8 @@ const tests = [
                `${prompt}555 + 909`,
                prev && '\n// 1464',
                `${prompt}let ab = 45`,
+               prompt,
+               `${prompt}let ab = 45`,
                `${prompt}555 + 909`,
                prev && '\n// 1464',
                `${prompt}{key : {key2 :[] }}`,
@@ -138,9 +139,12 @@ const tests = [
       // UP - skipping const foo = true
       '\x1B[1G', '\x1B[0J',
       '> 555 + 909', '\x1B[12G',
-      // UP, UP, ENTER. UPs at the end of the history have no effect.
-      '\r\n',
-      '1464\n',
+      // UP, UP
+      // UPs at the end of the history reset the line to the original input.
+      '\x1B[1G', '\x1B[0J',
+      '> 55', '\x1B[5G',
+      // ENTER
+      '\r\n', '55\n',
       '\x1B[1G', '\x1B[0J',
       '> ', '\x1B[3G',
       '\r\n'

diff --git a/test/parallel/test-repl-persistent-history.js b/test/parallel/test-repl-persistent-history.js
@@ -10,6 +10,7 @@ const assert = require('assert');
 const fs = require('fs');
 const path = require('path');
 const os = require('os');
+const util = require('util');
 
 const tmpdir = require('../common/tmpdir');
 tmpdir.refresh();
@@ -51,6 +52,7 @@ ActionStream.prototype.readable = true;
 
 // Mock keys
 const UP = { name: 'up' };
+const DOWN = { name: 'down' };
 const ENTER = { name: 'enter' };
 const CLEAR = { ctrl: true, name: 'u' };
 
@@ -90,20 +92,42 @@ const tests = [
   },
   {
     env: {},
-    test: [UP, '\'42\'', ENTER],
-    expected: [prompt, '\'', '4', '2', '\'', '\'42\'\n', prompt, prompt],
+    test: [UP, '21', ENTER, "'42'", ENTER],
+    expected: [
+      prompt,
+      '2', '1', '21\n', prompt, prompt,
+      "'", '4', '2', "'", "'42'\n", prompt, prompt
+    ],
     clean: false
   },
   { // Requires the above test case
     env: {},
-    test: [UP, UP, ENTER],
-    expected: [prompt, `${prompt}'42'`, '\'42\'\n', prompt]
+    test: [UP, UP, CLEAR, ENTER, DOWN, CLEAR, ENTER, UP, ENTER],
+    expected: [
+      prompt,
+      `${prompt}'42'`,
+      `${prompt}21`,
+      prompt,
+      prompt,
+      `${prompt}'42'`,
+      prompt,
+      prompt,
+      `${prompt}21`,
+      '21\n',
+      prompt,
+    ]
   },
   {
     env: { NODE_REPL_HISTORY: historyPath,
            NODE_REPL_HISTORY_SIZE: 1 },
-    test: [UP, UP, CLEAR],
-    expected: [prompt, `${prompt}'you look fabulous today'`, prompt]
+    test: [UP, UP, DOWN, CLEAR],
+    expected: [
+      prompt,
+      `${prompt}'you look fabulous today'`,
+      prompt,
+      `${prompt}'you look fabulous today'`,
+      prompt
+    ]
   },
   {
     env: { NODE_REPL_HISTORY: historyPathFail,
@@ -169,6 +193,8 @@ function runTest(assertCleaned) {
   const opts = tests.shift();
   if (!opts) return; // All done
 
+  console.log('NEW');
+
   if (assertCleaned) {
     try {
       assert.strictEqual(fs.readFileSync(defaultHistoryPath, 'utf8'), '');
@@ -193,6 +219,7 @@ function runTest(assertCleaned) {
     output: new stream.Writable({
       write(chunk, _, next) {
         const output = chunk.toString();
+        console.log('INPUT', util.inspect(output));
 
         // Ignore escapes and blank lines
         if (output.charCodeAt(0) === 27 || /^[\r\n]+$/.test(output))
@@ -207,7 +234,7 @@ function runTest(assertCleaned) {
         next();
       }
     }),
-    prompt: prompt,
+    prompt,
     useColors: false,
     terminal: true
   }, function(err, repl) {

diff --git a/test/parallel/test-repl-programmatic-history.js b/test/parallel/test-repl-programmatic-history.js
@@ -8,6 +8,7 @@ const assert = require('assert');
 const fs = require('fs');
 const path = require('path');
 const os = require('os');
+const util = require('util');
 
 const tmpdir = require('../common/tmpdir');
 tmpdir.refresh();
@@ -49,6 +50,7 @@ ActionStream.prototype.readable = true;
 
 // Mock keys
 const UP = { name: 'up' };
+const DOWN = { name: 'down' };
 const ENTER = { name: 'enter' };
 const CLEAR = { ctrl: true, name: 'u' };
 
@@ -88,20 +90,40 @@ const tests = [
   },
   {
     env: {},
-    test: [UP, '\'42\'', ENTER],
-    expected: [prompt, '\'', '4', '2', '\'', '\'42\'\n', prompt, prompt],
+    test: [UP, '21', ENTER, "'42'", ENTER],
+    expected: [
+      prompt,
+      // TODO(BridgeAR): The line is refreshed too many times. The double prompt
+      // is redundant and can be optimized away.
+      '2', '1', '21\n', prompt, prompt,
+      "'", '4', '2', "'", "'42'\n", prompt, prompt
+    ],
     clean: false
   },
   { // Requires the above test case
     env: {},
-    test: [UP, UP, ENTER],
-    expected: [prompt, `${prompt}'42'`, '\'42\'\n', prompt]
+    test: [UP, UP, UP, DOWN, ENTER],
+    expected: [
+      prompt,
+      `${prompt}'42'`,
+      `${prompt}21`,
+      prompt,
+      `${prompt}21`,
+      '21\n',
+      prompt
+    ]
   },
   {
     env: { NODE_REPL_HISTORY: historyPath,
            NODE_REPL_HISTORY_SIZE: 1 },
-    test: [UP, UP, CLEAR],
-    expected: [prompt, `${prompt}'you look fabulous today'`, prompt]
+    test: [UP, UP, DOWN, CLEAR],
+    expected: [
+      prompt,
+      `${prompt}'you look fabulous today'`,
+      prompt,
+      `${prompt}'you look fabulous today'`,
+      prompt
+    ]
   },
   {
     env: { NODE_REPL_HISTORY: historyPathFail,
@@ -167,6 +189,8 @@ function runTest(assertCleaned) {
   const opts = tests.shift();
   if (!opts) return; // All done
 
+  console.log('NEW');
+
   if (assertCleaned) {
     try {
       assert.strictEqual(fs.readFileSync(defaultHistoryPath, 'utf8'), '');
@@ -192,6 +216,7 @@ function runTest(assertCleaned) {
     output: new stream.Writable({
       write(chunk, _, next) {
         const output = chunk.toString();
+        console.log('INPUT', util.inspect(output));
 
         // Ignore escapes and blank lines
         if (output.charCodeAt(0) === 27 || /^[\r\n]+$/.test(output))