repl: add support for multiline history

lib/internal/readline/interface.js

@@ -25,6 +25,7 @@ const {
   StringPrototypeCodePointAt,
   StringPrototypeEndsWith,
   StringPrototypeRepeat,
+  StringPrototypeReplaceAll,
   StringPrototypeSlice,
   StringPrototypeStartsWith,
   StringPrototypeTrim,
@@ -950,7 +951,7 @@ class Interface extends InterfaceConstructor {
       if (index === -1) {
         this.line = search;
       } else {
-        this.line = this.history[index];
+        this.line = StringPrototypeReplaceAll(this.history[index], '\r', '\n');
       }
       this.historyIndex = index;
       this.cursor = this.line.length; // Set cursor to end of line.
@@ -973,7 +974,7 @@ class Interface extends InterfaceConstructor {
       if (index === this.history.length) {
         this.line = search;
       } else {
-        this.line = this.history[index];
+        this.line = StringPrototypeReplaceAll(this.history[index], '\r', '\n');
       }
       this.historyIndex = index;
       this.cursor = this.line.length; // Set cursor to end of line.

lib/internal/repl/history.js

@@ -97,7 +97,7 @@ function setupHistory(repl, historyPath, ready) {
     }
 
     if (data) {
-      repl.history = RegExpPrototypeSymbolSplit(/[\n\r]+/, data, repl.historySize);
+      repl.history = RegExpPrototypeSymbolSplit(/[\n]+/, data, repl.historySize);
     } else {
       repl.history = [];
     }

lib/repl.js

@@ -83,7 +83,9 @@ const {
   StringPrototypeCodePointAt,
   StringPrototypeEndsWith,
   StringPrototypeIncludes,
+  StringPrototypeIndexOf,
   StringPrototypeRepeat,
+  StringPrototypeReplaceAll,
   StringPrototypeSlice,
   StringPrototypeSplit,
   StringPrototypeStartsWith,
@@ -952,6 +954,22 @@ function REPLServer(prompt,
         self._domain.emit('error', e.err || e);
       }
 
+      // In the next two if blocks, we do not use os.EOL instead of '\n'
+      // because on Windows it is '\r\n'
+      if (cmd && StringPrototypeIndexOf(cmd, '\n') !== -1) { // If you are editing a multiline command
+        self.history[0] = StringPrototypeReplaceAll(cmd, '\n', '\r');
+      } else if (self[kBufferedCommandSymbol]) { // If a new multiline command was entered
+        // Remove the first N lines from the self.history array
+        // where N is the number of lines in the buffered command
+
+        const lines = StringPrototypeSplit(self[kBufferedCommandSymbol], '\n');
+        self.history = ArrayPrototypeSlice(self.history, lines.length);
+        ArrayPrototypePop(lines);
+        // And replace them with the single command split by '\r'
+        ArrayPrototypePush(lines, cmd);
+        ArrayPrototypeUnshift(self.history, ArrayPrototypeJoin(lines, '\r'));
+      }
+
       // Clear buffer if no SyntaxErrors
       self.clearBufferedCommand();
       sawCtrlD = false;

test/fixtures/.node_repl_history-multiline

@@ -0,0 +1,4 @@
+var d = [  {    a: 1,    b: 2,  },  {    a: 3,    b: 4,    c: [{ a: 1, b: 2 },      {        a: 3,        b: 4,      }    ]  }]
+const c = [  {    a: 1,    b: 2,  }]
+`const b = [  1,  2,  3,  4,]`
+a = `I am a multiline stringI can be as long as I want`

test/parallel/test-repl-history-navigation.js

@@ -633,6 +633,42 @@ const tests = [
     ],
     clean: false
   },
+  {
+    // Test that the multiline history is correctly navigated and it can be edited
+    env: { NODE_REPL_HISTORY: defaultHistoryPath },
+    skip: !process.features.inspector,
+    test: [
+      'let a = ``',
+      ENTER,
+      'a = `I am a multiline strong',
+      ENTER,
+      'which ends here`',
+      ENTER,
+      UP,
+      // press LEFT 19 times to reach the typo
+      ...Array(19).fill(LEFT),
+      BACKSPACE,
+      'i',
+      ENTER,
+    ],
+    expected: [
+      prompt, ...'let a = ``',
+      'undefined\n',
+      prompt, ...'a = `I am a multiline strong',
+      '... ',
+      ...'which ends here`',
+      "'I am a multiline strong\\nwhich ends here'\n",
+      prompt,
+      `${prompt}a = \`I am a multiline strong\nwhich ends here\``,
+      `${prompt}a = \`I am a multiline strong\nwhich ends here\``,
+      `${prompt}a = \`I am a multiline strng\nwhich ends here\``,
+      `${prompt}a = \`I am a multiline string\nwhich ends here\``,
+      `${prompt}a = \`I am a multiline string\nwhich ends here\``,
+      "'I am a multiline string\\nwhich ends here'\n",
+      prompt,
+    ],
+    clean: true
+  },
 ];
 const numtests = tests.length;
 

test/parallel/test-repl-load-multiline-from-history.js

@@ -0,0 +1,90 @@
+'use strict';
+
+// Flags: --expose-internals
+
+const common = require('../common');
+
+const assert = require('assert');
+const repl = require('internal/repl');
+const stream = require('stream');
+const fixtures = require('../common/fixtures');
+
+class ActionStream extends stream.Stream {
+  run(data) {
+    const _iter = data[Symbol.iterator]();
+    const doAction = () => {
+      const next = _iter.next();
+      if (next.done) {
+        // Close the repl. Note that it must have a clean prompt to do so.
+        this.emit('keypress', '', { ctrl: true, name: 'd' });
+        return;
+      }
+      const action = next.value;
+
+      if (typeof action === 'object') {
+        this.emit('keypress', '', action);
+      }
+      setImmediate(doAction);
+    };
+    doAction();
+  }
+  resume() {}
+  pause() {}
+}
+ActionStream.prototype.readable = true;
+
+{
+  // Testing multiline history loading
+  const tmpdir = require('../common/tmpdir');
+  tmpdir.refresh();
+  const replHistoryPath = fixtures.path('.node_repl_history-multiline');
+
+  const checkResults = common.mustSucceed((r) => {
+    assert.strictEqual(r.history.length, 4);
+
+    r.input.run([{ name: 'up' }]);
+    assert.strictEqual(
+      r.line,
+      'var d = [\n' +
+    '  {\n' +
+    '    a: 1,\n' +
+    '    b: 2,\n' +
+    '  },\n' +
+    '  {\n' +
+    '    a: 3,\n' +
+    '    b: 4,\n' +
+    '    c: [{ a: 1, b: 2 },\n' +
+    '      {\n' +
+    '        a: 3,\n' +
+    '        b: 4,\n' +
+    '      }\n' +
+    '    ]\n' +
+    '  }\n' +
+    ']'
+    );
+
+    r.input.run([{ name: 'up' }]);
+    assert.strictEqual(r.line, 'const c = [\n  {\n    a: 1,\n    b: 2,\n  }\n]');
+
+    r.input.run([{ name: 'up' }]);
+    assert.strictEqual(r.line, '`const b = [\n  1,\n  2,\n  3,\n  4,\n]`');
+
+    r.input.run([{ name: 'up' }]);
+    assert.strictEqual(r.line, 'a = `\nI am a multiline string\nI can be as long as I want`');
+
+  });
+
+  repl.createInternalRepl(
+    { NODE_REPL_HISTORY: replHistoryPath },
+    {
+      terminal: true,
+      input: new ActionStream(),
+      output: new stream.Writable({
+        write(chunk, _, next) {
+          next();
+        }
+      }),
+    },
+    checkResults
+  );
+}