8241950: JShell could support auto-indent

Reviewed-by: rfield

src/jdk.jshell/share/classes/jdk/internal/jshell/tool/ConsoleIOContext.java

@@ -25,7 +25,6 @@
 
 package jdk.internal.jshell.tool;
 
-
 import jdk.jshell.SourceCodeAnalysis.Documentation;
 import jdk.jshell.SourceCodeAnalysis.QualifiedNames;
 import jdk.jshell.SourceCodeAnalysis.Suggestion;
@@ -146,13 +145,34 @@ class ConsoleIOContext extends IOContext {
                 completionState.actionCount++;
                 return super.readBinding(keys, local);
             }
+            @Override
+            protected boolean insertCloseParen() {
+                Object oldIndent = getVariable(INDENTATION);
+                try {
+                    setVariable(INDENTATION, 0);
+                    return super.insertCloseParen();
+                } finally {
+                    setVariable(INDENTATION, oldIndent);
+                }
+            }
+            @Override
+            protected boolean insertCloseSquare() {
+                Object oldIndent = getVariable(INDENTATION);
+                try {
+                    setVariable(INDENTATION, 0);
+                    return super.insertCloseSquare();
+                } finally {
+                    setVariable(INDENTATION, oldIndent);
+                }
+            }
         };
 
         reader.setOpt(Option.DISABLE_EVENT_EXPANSION);
 
         reader.setParser((line, cursor, context) -> {
             if (!allowIncompleteInputs && !repl.isComplete(line)) {
-                throw new EOFError(cursor, cursor, line);
+                int pendingBraces = countPendingOpenBraces(line);
+                throw new EOFError(cursor, cursor, line, null, pendingBraces, null);
             }
             return new ArgumentLine(line, cursor);
         });
@@ -283,6 +303,11 @@ class ConsoleIOContext extends IOContext {
         return count;
     }
 
+    @Override
+    public void setIndent(int indent) {
+        in.variable(LineReader.INDENTATION, indent);
+    }
+
     private static final String FIXES_SHORTCUT = "\033\133\132"; //Shift-TAB
 
     private static final String LINE_SEPARATOR = System.getProperty("line.separator");
@@ -937,6 +962,25 @@ class ConsoleIOContext extends IOContext {
         return inputBytes[inputBytesPointer++];
     }
 
+    private int countPendingOpenBraces(String code) {
+        int pendingBraces = 0;
+        com.sun.tools.javac.util.Context ctx =
+                new com.sun.tools.javac.util.Context();
+        com.sun.tools.javac.parser.ScannerFactory scannerFactory =
+                com.sun.tools.javac.parser.ScannerFactory.instance(ctx);
+        com.sun.tools.javac.parser.Scanner scanner =
+                scannerFactory.newScanner(code, false);
+
+        while (true) {
+            switch (scanner.token().kind) {
+                case LBRACE: pendingBraces++; break;
+                case RBRACE: pendingBraces--; break;
+                case EOF: return pendingBraces;
+            }
+            scanner.nextToken();
+        }
+    }
+
     /**
      * A possible action which the user can choose to perform.
      */

src/jdk.jshell/share/classes/jdk/internal/jshell/tool/IOContext.java

@@ -56,6 +56,8 @@ abstract class IOContext implements AutoCloseable {
 
     public abstract int readUserInput() throws IOException;
 
+    public void setIndent(int indent) {}
+
     class InputInterruptedException extends Exception {
         private static final long serialVersionUID = 1L;
     }

src/jdk.jshell/share/classes/jdk/internal/jshell/tool/JShellTool.java

@@ -230,15 +230,17 @@ public class JShellTool implements MessageHandler {
 
     static final String STARTUP_KEY  = "STARTUP";
     static final String EDITOR_KEY   = "EDITOR";
-    static final String FEEDBACK_KEY = "FEEDBACK";
     static final String MODE_KEY     = "MODE";
+    static final String FEEDBACK_KEY = "FEEDBACK";
     static final String REPLAY_RESTORE_KEY = "REPLAY_RESTORE";
+    public static final String INDENT_KEY   = "INDENT";
 
     static final Pattern BUILTIN_FILE_PATTERN = Pattern.compile("\\w+");
     static final String BUILTIN_FILE_PATH_FORMAT = "/jdk/jshell/tool/resources/%s.jsh";
     static final String INT_PREFIX = "int $$exit$$ = ";
 
     static final int OUTPUT_WIDTH = 72;
+    static final int DEFAULT_INDENT = 4;
 
     // match anything followed by whitespace
     private static final Pattern OPTION_PRE_PATTERN =
@@ -910,6 +912,12 @@ public class JShellTool implements MessageHandler {
         }
     }
 
+    private String indent() {
+        String indentValue = prefs.get(INDENT_KEY);
+        if (indentValue == null) indentValue = Integer.toString(DEFAULT_INDENT);
+        return indentValue;
+    }
+
     /**
      * The entry point into the JShell tool.
      *
@@ -968,6 +976,14 @@ public class JShellTool implements MessageHandler {
             Runtime.getRuntime().addShutdownHook(shutdownHook);
             // execute from user input
             try (IOContext in = new ConsoleIOContext(this, cmdin, console)) {
+                int indent;
+                try {
+                    String indentValue = indent();
+                    indent = Integer.parseInt(indentValue);
+                } catch (NumberFormatException ex) {
+                    indent = DEFAULT_INDENT;
+                }
+                in.setIndent(indent);
                 while (regenerateOnDeath) {
                     if (!live) {
                         resetState();
@@ -1830,7 +1846,8 @@ public class JShellTool implements MessageHandler {
                                 SET_MODE_OPTIONS_COMPLETION_PROVIDER)),
                         "prompt", feedback.modeCompletions(),
                         "editor", fileCompletions(Files::isExecutable),
-                        "start", FILE_COMPLETION_PROVIDER),
+                        "start", FILE_COMPLETION_PROVIDER,
+                        "indent", EMPTY_COMPLETION_PROVIDER),
                         STARTSWITH_MATCHER)));
         registerCommand(new Command("/?",
                 "help.quest",
@@ -1941,7 +1958,7 @@ public class JShellTool implements MessageHandler {
     // --- Command implementations ---
 
     private static final String[] SET_SUBCOMMANDS = new String[]{
-        "format", "truncation", "feedback", "mode", "prompt", "editor", "start"};
+        "format", "truncation", "feedback", "mode", "prompt", "editor", "start", "indent"};
 
     final boolean cmdSet(String arg) {
         String cmd = "/set";
@@ -1958,6 +1975,7 @@ public class JShellTool implements MessageHandler {
             case "_blank": {
                 // show top-level settings
                 new SetEditor().set();
+                showIndent();
                 showSetStart();
                 setFeedback(this, at); // no args so shows feedback setting
                 hardmsg("jshell.msg.set.show.mode.settings");
@@ -1978,6 +1996,23 @@ public class JShellTool implements MessageHandler {
                 return new SetEditor(at).set();
             case "start":
                 return setStart(at);
+            case "indent":
+                String value = at.next();
+                if (value != null) {
+                    try {
+                        int indent = Integer.parseInt(value);
+                        String indentValue = Integer.toString(indent);
+                        prefs.put(INDENT_KEY, indentValue);
+                        input.setIndent(indent);
+                        fluffmsg("jshell.msg.set.indent.set", indentValue);
+                    } catch (NumberFormatException ex) {
+                        errormsg("jshell.err.invalid.indent", value);
+                        return false;
+                    }
+                } else {
+                    showIndent();
+                }
+                return true;
             default:
                 errormsg("jshell.err.arg", cmd, at.val());
                 return false;
@@ -2252,6 +2287,10 @@ public class JShellTool implements MessageHandler {
         hard(sb.toString());
     }
 
+    private void showIndent() {
+        hard("/set indent %s", indent());
+    }
+
     boolean cmdDebug(String arg) {
         if (arg.isEmpty()) {
             debug = !debug;

src/jdk.jshell/share/classes/jdk/internal/jshell/tool/resources/l10n.properties

@@ -54,6 +54,8 @@ jshell.err.command.ambiguous = Command: ''{0}'' is ambiguous: {1}
 jshell.msg.set.restore = Setting new options and restoring state.
 jshell.msg.set.editor.set = Editor set to: {0}
 jshell.msg.set.editor.retain = Editor setting retained: {0}
+jshell.msg.set.indent.set = Indent level set to: {0}
+jshell.err.invalid.indent = Invalid indent level: {0}
 jshell.err.no.builtin.editor = Built-in editor not available.
 jshell.err.cant.launch.editor = Cannot launch built-in editor -- unexpected exception: {0}
 jshell.msg.try.set.editor = See ''/help /set editor'' to use external editor.
@@ -516,6 +518,8 @@ the command prompt, the feedback mode to use, or the format of output.\n\
      Set the maximum length of a displayed value\n\n\
 /set format <mode> <field> "<format>" <selector>...\n\t\
      Configure a feedback mode by setting the format of a field when the selector matches\n\n\
+/set indent <number>\n\t\
+     Set the number of spaces that should be used to automatically indent snippets\n\n\
 /set\n\t\
      Show editor, start, and feedback settings as /set commands.\n\t\
      To show the settings of any of the above, omit the set value\n\n\
@@ -1136,6 +1140,18 @@ More than one <file> may be specified, for example:\n\
 \n\t\
 /set start -retain DEFAULT PRINTING
 
+help.set.indent.summary =\
+Specify the number of spaces that should be used to indent snippets
+
+help.set.indent =\
+Specify the number of spaces that should be used to indent snippets:\n\
+\n\t\
+/set indent <number>\n\
+\n\
+Show the indent setting:\n\
+\n\t\
+/set indent\n\
+
 startup.feedback = \
 /set mode verbose -command    \n\
 \n\

test/langtools/jdk/jshell/CommandCompletionTest.java

@@ -182,9 +182,9 @@ public class CommandCompletionTest extends ReplToolTesting {
                 a -> assertCompletion(a, "/help /s|", false,
                 "/save ", "/set "),
                 a -> assertCompletion(a, "/help /set |", false,
-                "editor", "feedback", "format", "mode", "prompt", "start", "truncation"),
+                "editor", "feedback", "format", "indent", "mode", "prompt", "start", "truncation"),
                 a -> assertCompletion(a, "/help set |", false,
-                "editor", "feedback", "format", "mode", "prompt", "start", "truncation"),
+                "editor", "feedback", "format", "indent", "mode", "prompt", "start", "truncation"),
                 a -> assertCompletion(a, "/help /edit |", false),
                 a -> assertCompletion(a, "/help dr|", false,
                 "drop ")
@@ -354,7 +354,7 @@ public class CommandCompletionTest extends ReplToolTesting {
         String[] modesWithOptions = Stream.concat(Arrays.stream(options), Arrays.stream(modes)).sorted().toArray(String[]::new);
         test(false, new String[] {"--no-startup"},
                 a -> assertCompletion(a, "/se|", false, "/set "),
-                a -> assertCompletion(a, "/set |", false, "editor ", "feedback ", "format ", "mode ", "prompt ", "start ", "truncation "),
+                a -> assertCompletion(a, "/set |", false, "editor ", "feedback ", "format ", "indent ", "mode ", "prompt ", "start ", "truncation "),
 
                 // /set editor
                 a -> assertCompletion(a, "/set e|", false, "editor "),

test/langtools/jdk/jshell/HistoryUITest.java

@@ -54,7 +54,7 @@ public class HistoryUITest extends UITesting {
             waitOutput(out, PROMPT);
             inputSink.write(UP);
             waitOutput(out, "^void test2\\(\\) \\{\n" +
-                            CONTINUATION_PROMPT + "System.err.println\\(2\\);\n" +
+                            CONTINUATION_PROMPT + "    System.err.println\\(2\\);\n" +
                             CONTINUATION_PROMPT + "\\}");
             inputSink.write(UP);
             waitOutput(out, "^\u001b\\[A");
@@ -62,13 +62,13 @@ public class HistoryUITest extends UITesting {
             waitOutput(out, "^\u001b\\[A");
             inputSink.write(UP);
             waitOutput(out, "^\u001b\\[8C1\n" +
-                            "\u001b\\[19C1\n\u001b\\[C");
+                            "\u001b\\[23C1\n\u001b\\[C");
             inputSink.write(DOWN);
             waitOutput(out, "^\u001B\\[2A\u001b\\[8C2\n" +
-                            "\u001b\\[19C2\n\u001b\\[C");
+                            "\u001b\\[23C2\n\u001b\\[C");
             inputSink.write(UP);
             waitOutput(out, "^\u001b\\[A");
-            for (int i = 0; i < 19; i++) inputSink.write("\033[C");
+            for (int i = 0; i < 23; i++) inputSink.write("\033[C");
             waitOutput(out, "C");
             inputSink.write("\u0008\"Modified!\"\n");
             waitOutput(out, PROMPT);

test/langtools/jdk/jshell/IndentUITest.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2020, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8241950
+ * @summary Check the UI behavior of indentation
+ * @library /tools/lib
+ * @modules
+ *     jdk.compiler/com.sun.tools.javac.api
+ *     jdk.compiler/com.sun.tools.javac.main
+ *     jdk.jshell/jdk.internal.jshell.tool.resources:open
+ *     jdk.jshell/jdk.jshell:open
+ * @build toolbox.ToolBox toolbox.JarTask toolbox.JavacTask
+ * @build Compiler UITesting
+ * @compile IndentUITest.java
+ * @run testng IndentUITest
+ */
+
+import org.testng.annotations.Test;
+
+@Test
+public class IndentUITest extends UITesting {
+
+    public IndentUITest() {
+        super(true);
+    }
+
+    public void testIdent() throws Exception {
+        doRunTest((inputSink, out) -> {
+            inputSink.write("void test1() {\nSystem.err.println(1);\n}\n");
+            waitOutput(out, "void test1\\(\\)\u001B\\[2D\u001B\\[2C \\{\n" +
+                            CONTINUATION_PROMPT + "    System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
+                            CONTINUATION_PROMPT + "    \\}\u001B\\[2A\u001B\\[8C\n\n\u001B\\[K\\}\n" +
+                            "\u001B\\[\\?2004l\\|  created method test1\\(\\)\n" +
+                            "\u001B\\[\\?2004h" + PROMPT);
+            inputSink.write(UP);
+            waitOutput(out, "^void test1\\(\\) \\{\n" +
+                            CONTINUATION_PROMPT + "    System.err.println\\(1\\);\n" +
+                            CONTINUATION_PROMPT + "\\}");
+            inputSink.write(DOWN);
+            inputSink.write("/set indent 2\n");
+            inputSink.write("void test2() {\nSystem.err.println(1);\n}\n");
+            waitOutput(out, "void test2\\(\\)\u001B\\[2D\u001B\\[2C \\{\n" +
+                            CONTINUATION_PROMPT + "  System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
+                            CONTINUATION_PROMPT + "  \\}\u001B\\[2A\u001B\\[10C\n\n\u001B\\[K\\}\n" +
+                            "\u001B\\[\\?2004l\\|  created method test2\\(\\)\n" +
+                            "\u001B\\[\\?2004h" + PROMPT);
+            inputSink.write(UP);
+            waitOutput(out, "^void test2\\(\\) \\{\n" +
+                            CONTINUATION_PROMPT + "  System.err.println\\(1\\);\n" +
+                            CONTINUATION_PROMPT + "\\}");
+        });
+    }
+
+}

test/langtools/jdk/jshell/PasteAndMeasurementsUITest.java

@@ -62,12 +62,12 @@ public class PasteAndMeasurementsUITest extends UITesting {
             inputSink.write("void test1() {\nSystem.err.println(1);\n}\n" + //LOC +
                             "void test2() {\nSystem.err.println(1);\n}\n"/* + LOC + LOC + LOC + LOC + LOC*/);
             waitOutput(out,       "void test1\\(\\)\u001B\\[2D\u001B\\[2C \\{\n" +
-                            CONTINUATION_PROMPT + "System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
+                            CONTINUATION_PROMPT + "    System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
-                            CONTINUATION_PROMPT + "\\}\u001B\\[2A\u001B\\[12C\n\n\u001B\\[C\n" +
+                            CONTINUATION_PROMPT + "    \\}\u001B\\[2A\u001B\\[8C\n\n\u001B\\[K\\}\n" +
                             "\u001B\\[\\?2004l\\|  created method test1\\(\\)\n" +
                             "\u001B\\[\\?2004h" + PROMPT + "void test2\\(\\)\u001B\\[2D\u001B\\[2C \\{\n" +
-                            CONTINUATION_PROMPT + "System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
+                            CONTINUATION_PROMPT + "    System.err.println\\(1\\)\u001B\\[3D\u001B\\[3C;\n" +
-                            CONTINUATION_PROMPT + "\\}\u001B\\[2A\u001B\\[12C\n\n\u001B\\[C\n" +
+                            CONTINUATION_PROMPT + "    \\}\u001B\\[2A\u001B\\[8C\n\n\u001B\\[K\\}\n" +
                             "\u001B\\[\\?2004l\\|  created method test2\\(\\)\n" +
                             "\u001B\\[\\?2004h" + PROMPT);
         });

test/langtools/jdk/jshell/ReplToolTesting.java

@@ -268,6 +268,7 @@ public class ReplToolTesting {
     @BeforeMethod
     public void setUp() {
         prefsMap = new HashMap<>();
+        prefsMap.put("INDENT", "0");
         envvars = new HashMap<>();
         System.setProperty("jshell.test.allow.incomplete.inputs", "true");
     }

test/langtools/jdk/jshell/ToolBasicTest.java

@@ -879,4 +879,15 @@ public class ToolBasicTest extends ReplToolTesting {
         );
     }
 
+    public void testIndent() { //8223688
+        prefsMap.remove("INDENT");
+        test(false, new String[]{"--no-startup"},
+                a -> assertCommand(a, "/set indent", "|  /set indent 4"),
+                a -> assertCommand(a, "/set indent 2", "|  Indent level set to: 2"),
+                a -> assertCommand(a, "/set indent", "|  /set indent 2"),
+                a -> assertCommand(a, "/set indent broken", "|  Invalid indent level: broken"),
+                a -> assertCommandOutputContains(a, "/set", "|  /set indent 2")
+        );
+    }
+
 }