repl: add support for custom completions

Allow user code to override the default `complete()` function from `readline.Interface`. See: https://nodejs.org/api/readline.html#readline_use_of_the_completer_function Ref: nodejs/node-v0.x-archive#8484 PR-URL: #7527 Reviewed-By: James M Snell <[email protected]> Reviewed-By: Colin Ihrig <[email protected]> Reviewed-By: Lance Ball <[email protected]>

Author: diosney

doc/api/repl.md

@@ -382,6 +382,8 @@ added: v0.1.91
 `undefined`. Defaults to `false`.
 *`writer`{Function} The function to invoke to format the output of each
  command before writing to `output`. Defaults to [`util.inspect()`][].
+*`completer`{Function} An optional function used for custom Tab auto
+ completion. See [`readline.InterfaceCompleter`][] for an example.
 *`replMode` - A flag that specifies whether the default evaluator executes
  all JavaScript commands in strict mode, default mode, or a hybrid mode
  ("magic" mode.) Acceptable values are:
@@ -526,3 +528,4 @@ see: https://gist.github.com/2053342
 [`util.inspect()`]: util.html#util_util_inspect_object_options
 [here]: util.html#util_custom_inspect_function_on_objects
 [`readline.Interface`]: readline.html#readline_class_interface
+[`readline.InterfaceCompleter`]: readline.html#readline_use_of_the_completer_function

lib/repl.js

@@ -386,14 +386,15 @@ function REPLServer(prompt,
 self.bufferedCommand='';
 self.lines.level=[];
 
-functioncomplete(text,callback){
-self.complete(text,callback);
-}
+// Figure out which "complete" function to use.
+self.completer=(typeofoptions.completer==='function')
+ ? options.completer
+ : complete;
 
 Interface.call(this,{
 input: self.inputStream,
 output: self.outputStream,
-completer: complete,
+completer: self.completer,
 terminal: options.terminal,
 historySize: options.historySize,
  prompt
@@ -706,6 +707,10 @@ function filteredOwnPropertyNames(obj){
 returnObject.getOwnPropertyNames(obj).filter(intFilter);
 }
 
+REPLServer.prototype.complete=function(){
+this.completer.apply(this,arguments);
+};
+
 // Provide a list of completions for the given leading text. This is
 // given to the readline interface for handling tab completion.
 //
@@ -716,7 +721,7 @@ function filteredOwnPropertyNames(obj){
 //
 // Warning: This eval's code like "foo.bar.baz", so it will run property
 // getter code.
-REPLServer.prototype.complete=function(line,callback){
+functioncomplete(line,callback){
 // There may be local variables to evaluate, try a nested REPL
 if(this.bufferedCommand!==undefined&&this.bufferedCommand.length){
 // Get a new array of inputed lines
@@ -975,7 +980,7 @@ REPLServer.prototype.complete = function(line, callback){
 
 callback(null,[completions||[],completeOn]);
 }
-};
+}
 
 
 /**

test/parallel/test-repl-tab-complete.js

@@ -32,7 +32,7 @@ testMe.complete('console.lo', common.mustCall(function(error, data){
 assert.deepStrictEqual(data,[['console.log'],'console.lo']);
 }));
 
-// Tab Complete will return globaly scoped variables
+// Tab Complete will return globally scoped variables
 putIn.run(['};']);
 testMe.complete('inner.o',common.mustCall(function(error,data){
 assert.deepStrictEqual(data,works);
@@ -283,3 +283,68 @@ if (typeof Intl === 'object'){
 testNonGlobal.complete('I',common.mustCall((error,data)=>{
 assert.deepStrictEqual(data,builtins);
 }));
+
+// To test custom completer function.
+// Sync mode.
+constcustomCompletions='aaa aa1 aa2 bbb bb1 bb2 bb3 ccc ddd eee'.split(' ');
+consttestCustomCompleterSyncMode=repl.start({
+prompt: '',
+input: putIn,
+output: putIn,
+completer: functioncompleterSyncMode(line){
+consthits=customCompletions.filter((c)=>{
+returnc.indexOf(line)===0;
+});
+// Show all completions if none found.
+return[hits.length ? hits : customCompletions,line];
+}
+});
+
+// On empty line should output all the custom completions
+// without complete anything.
+testCustomCompleterSyncMode.complete('',common.mustCall((error,data)=>{
+assert.deepStrictEqual(data,[
+customCompletions,
+''
+]);
+}));
+
+// On `a` should output `aaa aa1 aa2` and complete until `aa`.
+testCustomCompleterSyncMode.complete('a',common.mustCall((error,data)=>{
+assert.deepStrictEqual(data,[
+'aaa aa1 aa2'.split(' '),
+'a'
+]);
+}));
+
+// To test custom completer function.
+// Async mode.
+consttestCustomCompleterAsyncMode=repl.start({
+prompt: '',
+input: putIn,
+output: putIn,
+completer: functioncompleterAsyncMode(line,callback){
+consthits=customCompletions.filter((c)=>{
+returnc.indexOf(line)===0;
+});
+// Show all completions if none found.
+callback(null,[hits.length ? hits : customCompletions,line]);
+}
+});
+
+// On empty line should output all the custom completions
+// without complete anything.
+testCustomCompleterAsyncMode.complete('',common.mustCall((error,data)=>{
+assert.deepStrictEqual(data,[
+customCompletions,
+''
+]);
+}));
+
+// On `a` should output `aaa aa1 aa2` and complete until `aa`.
+testCustomCompleterAsyncMode.complete('a',common.mustCall((error,data)=>{
+assert.deepStrictEqual(data,[
+'aaa aa1 aa2'.split(' '),
+'a'
+]);
+}));