Add colors to the interactive interpreter

src/interpreter/InteractiveLispInterpreter.java

@@ -1,7 +1,5 @@
 package interpreter;
 
-import sexpression.SExpression;
-
 public class InteractiveLispInterpreter extends LispInterpreter {
 
     private static final String PROMPT = "~ ";
@@ -13,9 +11,9 @@ public class InteractiveLispInterpreter extends LispInterpreter {
     }
 
     @Override
-    protected void printSExpression(SExpression sExpression) {
+    protected void evaluateAndPrintNextSExpression() {
         environment.getOutput().println();
-        super.printSExpression(sExpression);
+        super.evaluateAndPrintNextSExpression();
     }
 
     @Override

src/interpreter/LispInterpreter.java

@@ -31,7 +31,7 @@ public class LispInterpreter {
 
     protected void prompt() {}
 
-    private void evaluateAndPrintNextSExpression() {
+    protected void evaluateAndPrintNextSExpression() {
         try {
             evaluateAndPrintNextSExpressionWithException();
         } catch (LispException e) {

src/main/LispMain.java

@@ -9,7 +9,7 @@ import com.googlecode.lanterna.terminal.*;
 
 import interpreter.*;
 import terminal.LispTerminal;
-import terminal.SafeStream.SafePipedOutputStream;
+import terminal.SafeStream.SafeOutputStream;
 import terminal.SafeStream.UncheckedIOException;
 
 public class LispMain {
@@ -35,7 +35,7 @@ public class LispMain {
     private PipedInputStream outputReader;
     private PipedOutputStream outputWriter;
     private PrintStream outputStream;
-    private SafePipedOutputStream safeOutputWriter;
+    private SafeOutputStream safeOutputWriter;
     private LispTerminal lispTerminal;
 
     private void runInteractive() {
@@ -60,7 +60,7 @@ public class LispMain {
         outputReader = new PipedInputStream();
         outputWriter = new PipedOutputStream(outputReader);
         outputStream = new PrintStream(outputWriter);
-        safeOutputWriter = new SafePipedOutputStream(outputWriter);
+        safeOutputWriter = new SafeOutputStream(outputWriter);
         lispTerminal = new LispTerminal(createIOSafeTerminal(), inputWriter, outputReader);
     }
 
@@ -82,11 +82,11 @@ public class LispMain {
         builder.setErrorOutput(outputStream);
         builder.setTerminationFunction(this::shutdown);
         builder.setErrorTerminationFunction(this::shutdown);
-        builder.setPromptDecorator(makeSegmentDecorator(ANSI_GREEN));
+        builder.setPromptDecorator(s -> s + END_OF_SEGMENT);
-        builder.setValueOutputDecorator(s -> s);
+        builder.setValueOutputDecorator(makeColorDecorator(ANSI_GREEN));
-        builder.setWarningOutputDecorator(s -> s);
+        builder.setWarningOutputDecorator(makeColorDecorator(ANSI_YELLOW));
-        builder.setErrorOutputDecorator(s -> s);
+        builder.setErrorOutputDecorator(makeColorDecorator(ANSI_RED));
-        builder.setCriticalOutputDecorator(s -> s);
+        builder.setCriticalOutputDecorator(makeColorDecorator(ANSI_PURPLE));
 
         return builder.build();
     }
@@ -98,16 +98,6 @@ public class LispMain {
         safeOutputWriter.close();
     }
 
-    private static Function<String, String> makeSegmentDecorator(String color) {
-        return new Function<String, String>() {
-
-            @Override
-            public String apply(String s) {
-                return s + END_OF_SEGMENT;
-            }
-        };
-    }
-
     private void runWithFile(String fileName) {
         buildFileInterpreter(fileName).interpret();
     }

src/terminal/ControlSequence.java

@@ -0,0 +1,14 @@
+package terminal;
+
+import com.googlecode.lanterna.terminal.IOSafeTerminal;
+
+public interface ControlSequence {
+
+    default String getCode() {
+        return "";
+    }
+
+    default void applyTo(IOSafeTerminal terminal) {}
+
+    public static class NullControlSequence implements ControlSequence {}
+}

src/terminal/ControlSequenceHandler.java

@@ -1,25 +1,63 @@
 package terminal;
 
-import static terminal.ControlSequenceHandler.Command.SGR;
+import static java.lang.Character.isDigit;
+import static terminal.ControlSequenceLookup.lookupControlSequence;
+import static util.Characters.*;
+
+import terminal.SafeStream.SafeInputStream;
 
 class ControlSequenceHandler {
 
+    private static final char ESCAPE = '\u001B';
+
     public static final boolean isEscape(char c) {
-        return c == '\u001B';
+        return c == ESCAPE;
     }
 
-    private boolean inControlSequence;
+    private SafeInputStream input;
-    private int code;
+    private String code;
-    private Command command;
+    private int currentCharacter;
 
     public ControlSequenceHandler() {
-        this.inControlSequence = false;
+        this.input = null;
-        this.code = 0;
+        this.code = "";
-        this.command = SGR;
+        this.currentCharacter = 0;
     }
 
-    public static enum Command {
+    public ControlSequence parse(SafeInputStream inputStream) {
-        SGR
+        input = inputStream;
+        code = "";
+
+        readCharacter();
+        if (isExpectedFirstCharacter())
+            readCode();
+
+        return lookupControlSequence((char) currentCharacter, code);
+    }
+
+    private void readCharacter() {
+        currentCharacter = input.read();
+    }
+
+    private boolean isExpectedFirstCharacter() {
+        return isCharacter() && isLeftBracket();
+    }
+
+    private boolean isCharacter() {
+        return currentCharacter != EOF;
+    }
+
+    private boolean isLeftBracket() {
+        return (char) currentCharacter == LEFT_SQUARE_BRACKET;
+    }
+
+    private void readCode() {
+        for (readCharacter(); isPartOfCode(); readCharacter())
+            code += (char) currentCharacter;
+    }
+
+    private boolean isPartOfCode() {
+        return isCharacter() && isDigit((char) currentCharacter);
     }
 
 }

src/terminal/ControlSequenceLookup.java

@@ -0,0 +1,28 @@
+package terminal;
+
+import static terminal.SelectGraphicRendition.SGR_COMMAND;
+
+import java.util.*;
+
+import terminal.ControlSequence.NullControlSequence;
+
+public class ControlSequenceLookup {
+
+    private static Map<Character, Map<String, ControlSequence>> controlSequenceMap = new HashMap<>();
+
+    static {
+        Map<String, ControlSequence> selectGraphicRenditionMap = new HashMap<>();
+
+        for (SelectGraphicRendition sgr : SelectGraphicRendition.values())
+            selectGraphicRenditionMap.put(sgr.getCode(), sgr);
+
+        controlSequenceMap.put(SGR_COMMAND, selectGraphicRenditionMap);
+    }
+
+    public static ControlSequence lookupControlSequence(char command, String code) {
+        Map<String, ControlSequence> commandMap = controlSequenceMap.getOrDefault(command, new HashMap<>());
+
+        return commandMap.getOrDefault(code, new NullControlSequence());
+    }
+
+}

src/terminal/LispTerminal.java

@@ -18,10 +18,10 @@ public class LispTerminal {
     public static final char END_OF_SEGMENT = 'x';
 
     private IOSafeTerminal terminal;
-    private SafePipedOutputStream inputWriter;
+    private SafeOutputStream inputWriter;
-    private SafePipedInputStream outputReader;
+    private SafeInputStream outputReader;
-    private ExecutorService executorService;
     private ControlSequenceHandler controlSequenceHandler;
+    private ExecutorService executorService;
     private TerminalSize terminalSize;
     private String inputLine;
     private String outputSegment;
@@ -31,20 +31,20 @@ public class LispTerminal {
 
     public LispTerminal(IOSafeTerminal terminal, PipedOutputStream inputWriter, PipedInputStream outputReader) {
         this.terminal = terminal;
-        this.inputWriter = new SafePipedOutputStream(inputWriter);
+        this.inputWriter = new SafeOutputStream(inputWriter);
-        this.outputReader = new SafePipedInputStream(outputReader);
+        this.outputReader = new SafeInputStream(outputReader);
-        this.executorService = Executors.newFixedThreadPool(2);
         this.controlSequenceHandler = new ControlSequenceHandler();
+        this.executorService = Executors.newFixedThreadPool(2);
         this.terminalSize = terminal.getTerminalSize();
         this.inputLine = "";
         this.outputSegment = "";
         this.isStopped = false;
 
-        updateOrigin();
+        setOriginToCurrentPosition();
         terminal.addResizeListener((t, newSize) -> resize());
     }
 
-    private synchronized void updateOrigin() {
+    private synchronized void setOriginToCurrentPosition() {
         TerminalPosition cursorPosition = terminal.getCursorPosition();
         originColumn = cursorPosition.getColumn();
         originRow = cursorPosition.getRow();
@@ -54,12 +54,12 @@ public class LispTerminal {
         terminalSize = terminal.getTerminalSize();
         terminal.clearScreen();
         terminal.setCursorPosition(0, 0);
-        updateOrigin();
+        setOriginToCurrentPosition();
-        putString(inputLine);
+        putStringToTerminal(inputLine);
         moveCursorToEndOfInput();
     }
 
-    private synchronized void putString(String characters) {
+    private synchronized void putStringToTerminal(String characters) {
         for (char c : characters.toCharArray())
             terminal.putCharacter(c);
     }
@@ -113,7 +113,7 @@ public class LispTerminal {
     private void doControlC() {
         moveCursorToEndOfInput();
         terminal.putCharacter('\n');
-        updateOrigin();
+        setOriginToCurrentPosition();
         stop();
     }
 
@@ -170,7 +170,7 @@ public class LispTerminal {
         inputWriter.write(inputLine.getBytes());
         inputWriter.flush();
         inputLine = "";
-        updateOrigin();
+        setOriginToCurrentPosition();
     }
 
     private synchronized void doLeftArrow() {
@@ -257,7 +257,7 @@ public class LispTerminal {
         String remaining = inputLine.substring(distanceFromOrigin, inputLine.length());
         inputLine = inputLine.substring(0, distanceFromOrigin - 1) + remaining;
         moveCursorLeft(cursorPosition);
-        putString(remaining + " ");
+        putStringToTerminal(remaining + " ");
         moveCursorLeft(cursorPosition);
     }
 
@@ -272,7 +272,7 @@ public class LispTerminal {
         int distanceFromOrigin = getDistanceFromOrigin(cursorPosition);
         String remaining = inputLine.substring(distanceFromOrigin + 1, inputLine.length());
         inputLine = inputLine.substring(0, distanceFromOrigin) + remaining;
-        putString(remaining + " ");
+        putStringToTerminal(remaining + " ");
         terminal.setCursorPosition(cursorPosition);
     }
 
@@ -299,7 +299,7 @@ public class LispTerminal {
         int distanceFromOrigin = getDistanceFromOrigin(cursorPosition);
         String remaining = character + inputLine.substring(distanceFromOrigin, inputLine.length());
         inputLine = inputLine.substring(0, distanceFromOrigin) + remaining;
-        putString(remaining);
+        putStringToTerminal(remaining);
         moveCursorRight(cursorPosition);
     }
 
@@ -316,7 +316,7 @@ public class LispTerminal {
 
     private synchronized TerminalPosition adjustCursorPosition(TerminalPosition cursorPosition) {
         terminal.setCursorPosition(new TerminalPosition(originColumn, originRow));
-        putString(inputLine);
+        putStringToTerminal(inputLine);
 
         return cursorPosition.withRelativeRow(-1);
     }
@@ -343,16 +343,12 @@ public class LispTerminal {
     }
 
     private synchronized void processOutput(char c) {
-        if (isEscape(c))
+        if (isEndOfSegment(c))
-            parseControlSequence();
-        else if (isEndOfSegment(c))
             writeSegment();
         else
             outputSegment += c;
     }
 
-    private synchronized void parseControlSequence() {}
-
     private synchronized boolean isEndOfSegment(char c) {
         return c == END_OF_SEGMENT;
     }
@@ -362,16 +358,31 @@ public class LispTerminal {
         printSegmentCharacters();
         terminal.setCursorVisible(true);
         outputSegment = "";
-        updateOrigin();
+        setOriginToCurrentPosition();
     }
 
     private synchronized void printSegmentCharacters() {
         moveCursorToEndOfInput();
-        putString(outputSegment);
+        putOutputToTerminal();
         moveCursorToNextRowIfNecessary();
         terminal.flush();
     }
 
+    private synchronized void putOutputToTerminal() {
+        SafeInputStream input = new SafeInputStream(new ByteArrayInputStream(outputSegment.getBytes()));
+
+        for (int c = input.read(); c != EOF; c = input.read())
+            if (isEscape((char) c))
+                applyControlSequence(input);
+            else
+                terminal.putCharacter((char) c);
+    }
+
+    private void applyControlSequence(SafeInputStream input) {
+        ControlSequence controlSequence = controlSequenceHandler.parse(input);
+        controlSequence.applyTo(terminal);
+    }
+
     private synchronized void moveCursorToNextRowIfNecessary() {
         TerminalPosition cursorPosition = terminal.getCursorPosition();
 

src/terminal/SafeStream.java

@@ -4,11 +4,11 @@ import java.io.*;
 
 public interface SafeStream {
 
-    public static class SafePipedInputStream {
+    public static class SafeInputStream {
 
-        private PipedInputStream underlyingStream;
+        private InputStream underlyingStream;
 
-        public SafePipedInputStream(PipedInputStream underlyingStream) {
+        public SafeInputStream(InputStream underlyingStream) {
             this.underlyingStream = underlyingStream;
         }
 
@@ -29,11 +29,11 @@ public interface SafeStream {
         }
     }
 
-    public static class SafePipedOutputStream {
+    public static class SafeOutputStream {
 
-        private PipedOutputStream underlyingStream;
+        private OutputStream underlyingStream;
 
-        public SafePipedOutputStream(PipedOutputStream underlyingStream) {
+        public SafeOutputStream(OutputStream underlyingStream) {
             this.underlyingStream = underlyingStream;
         }
 

src/terminal/SelectGraphicRendition.java

@@ -0,0 +1,75 @@
+package terminal;
+
+import com.googlecode.lanterna.TextColor;
+import com.googlecode.lanterna.terminal.IOSafeTerminal;
+
+public enum SelectGraphicRendition implements ControlSequence {
+
+    RESET {
+
+        @Override
+        public String getCode() {
+            return "0";
+        }
+
+        @Override
+        public void applyTo(IOSafeTerminal terminal) {
+            terminal.resetColorAndSGR();
+        }
+    },
+
+    RED {
+
+        @Override
+        public String getCode() {
+            return "31";
+        }
+
+        @Override
+        public void applyTo(IOSafeTerminal terminal) {
+            terminal.setForegroundColor(TextColor.ANSI.RED);
+        }
+    },
+
+    GREEN {
+
+        @Override
+        public String getCode() {
+            return "32";
+        }
+
+        @Override
+        public void applyTo(IOSafeTerminal terminal) {
+            terminal.setForegroundColor(TextColor.ANSI.GREEN);
+        }
+    },
+
+    YELLOW {
+
+        @Override
+        public String getCode() {
+            return "33";
+        }
+
+        @Override
+        public void applyTo(IOSafeTerminal terminal) {
+            terminal.setForegroundColor(TextColor.ANSI.YELLOW);
+        }
+    },
+
+    PURPLE {
+
+        @Override
+        public String getCode() {
+            return "35";
+        }
+
+        @Override
+        public void applyTo(IOSafeTerminal terminal) {
+            terminal.setForegroundColor(TextColor.ANSI.MAGENTA);
+        }
+    };
+
+    public static final char SGR_COMMAND = 'm';
+
+}

test/terminal/ControlSequenceHandlerTest.java

@@ -0,0 +1,129 @@
+package terminal;
+
+import static org.junit.Assert.*;
+import static terminal.ControlSequenceHandler.isEscape;
+import static terminal.SelectGraphicRendition.*;
+
+import org.junit.*;
+
+import terminal.ControlSequence.NullControlSequence;
+import terminal.SafeStream.SafeInputStream;
+import testutil.TestUtilities;
+import util.Characters;
+
+public class ControlSequenceHandlerTest {
+
+    private ControlSequenceHandler handler;
+
+    private Object readRemaining(SafeInputStream input) {
+        String remaining = "";
+
+        for (int c = input.read(); c != Characters.EOF; c = input.read())
+            remaining += (char) c;
+
+        return remaining;
+    }
+
+    private SafeInputStream createSafeInputStream(String data) {
+        return new SafeInputStream(TestUtilities.createInputStreamFromString(data));
+    }
+
+    @Before
+    public void setUp() {
+        handler = new ControlSequenceHandler();
+    }
+
+    @Test
+    public void isEscapeDetectsNonEscapeCharacter() {
+        assertFalse(isEscape('x'));
+    }
+
+    @Test
+    public void isEscapeDetectsEscapeCharacter() {
+        assertTrue(isEscape('\u001b'));
+    }
+
+    @Test
+    public void correctlyParsesControlSequence_LeavesRestOfStreamIntact() {
+        SafeInputStream input = createSafeInputStream("[32mdata");
+        handler.parse(input);
+        assertEquals("data", readRemaining(input));
+    }
+
+    @Test
+    public void unterminatedControlSequence_OnlyConsumesFirstNonSequenceCharacter() {
+        SafeInputStream input = createSafeInputStream("[32data");
+        handler.parse(input);
+        assertEquals("ata", readRemaining(input));
+    }
+
+    @Test
+    public void malformedControlSequence_OnlyConsumesOneCharacter() {
+        SafeInputStream input = createSafeInputStream("32mdata");
+        handler.parse(input);
+        assertEquals("2mdata", readRemaining(input));
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_EOF() {
+        SafeInputStream input = createSafeInputStream("");
+        assertTrue(handler.parse(input) instanceof NullControlSequence);
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_EOF_AfterFirstCharacter() {
+        SafeInputStream input = createSafeInputStream("[");
+        assertTrue(handler.parse(input) instanceof NullControlSequence);
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_UnterminatedControlSequence() {
+        SafeInputStream input = createSafeInputStream("[data");
+        assertTrue(handler.parse(input) instanceof NullControlSequence);
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_MalformedControlSequence() {
+        SafeInputStream input = createSafeInputStream("32mdata");
+        assertTrue(handler.parse(input) instanceof NullControlSequence);
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_SGR_Reset() {
+        SafeInputStream input = createSafeInputStream("[0m");
+        assertEquals(RESET, handler.parse(input));
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_SGR_Red() {
+        SafeInputStream input = createSafeInputStream("[31m");
+        assertEquals(RED, handler.parse(input));
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_SGR_Green() {
+        SafeInputStream input = createSafeInputStream("[32m");
+        assertEquals(GREEN, handler.parse(input));
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_SGR_Yellow() {
+        SafeInputStream input = createSafeInputStream("[33m");
+        assertEquals(YELLOW, handler.parse(input));
+    }
+
+    @Test
+    public void parsedControlSequenceIsCorrectType_SGR_Purple() {
+        SafeInputStream input = createSafeInputStream("[35m");
+        assertEquals(PURPLE, handler.parse(input));
+    }
+
+    @Test
+    public void parseMultipleControlSequences() {
+        SafeInputStream input = createSafeInputStream("[35m[32m[0m");
+        assertEquals(PURPLE, handler.parse(input));
+        assertEquals(GREEN, handler.parse(input));
+        assertEquals(RESET, handler.parse(input));
+    }
+
+}

test/terminal/ControlSequenceTest.java

@@ -0,0 +1,82 @@
+package terminal;
+
+import static org.junit.Assert.assertTrue;
+import static terminal.SelectGraphicRendition.*;
+
+import java.util.*;
+
+import org.junit.*;
+
+import com.googlecode.lanterna.TextColor;
+import com.googlecode.lanterna.terminal.virtual.*;
+
+import terminal.ControlSequence.NullControlSequence;
+
+public class ControlSequenceTest {
+
+    private Set<String> indicatorSet;
+
+    private VirtualTerminal createTerminalWithIndicators() {
+        return new DefaultVirtualTerminal() {
+
+            @Override
+            public void resetColorAndSGR() {
+                indicatorSet.add("RESET");
+            }
+
+            @Override
+            public void setForegroundColor(TextColor color) {
+                indicatorSet.add(color.toString());
+            }
+        };
+    }
+
+    @Before
+    public void setUp() {
+        indicatorSet = new HashSet<>();
+    }
+
+    @Test
+    public void nullControlSequenceDoesNothing() {
+        ControlSequence nullControlSequence = new NullControlSequence();
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        nullControlSequence.applyTo(terminal);
+        assertTrue(indicatorSet.isEmpty());
+    }
+
+    @Test
+    public void controlSequenceUpdatesTerminal_SGR_Reset() {
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        RESET.applyTo(terminal);
+        assertTrue(indicatorSet.contains("RESET"));
+    }
+
+    @Test
+    public void controlSequenceUpdatesTerminal_SGR_Red() {
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        RED.applyTo(terminal);
+        assertTrue(indicatorSet.contains("RED"));
+    }
+
+    @Test
+    public void controlSequenceUpdatesTerminal_SGR_Green() {
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        GREEN.applyTo(terminal);
+        assertTrue(indicatorSet.contains("GREEN"));
+    }
+
+    @Test
+    public void controlSequenceUpdatesTerminal_SGR_Yellow() {
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        YELLOW.applyTo(terminal);
+        assertTrue(indicatorSet.contains("YELLOW"));
+    }
+
+    @Test
+    public void controlSequenceUpdatesTerminal_SGR_Purple() {
+        VirtualTerminal terminal = createTerminalWithIndicators();
+        PURPLE.applyTo(terminal);
+        assertTrue(indicatorSet.contains("MAGENTA"));
+    }
+
+}

test/terminal/LispTerminalTest.java

@@ -508,4 +508,10 @@ public class LispTerminalTest {
         assertCharacterPositions(new char[][] { { ' ', ' ', ' ' }, { ' ', ' ', ' ' } });
     }
 
+    @Test
+    public void controlSequenceIsNotPrinted() {
+        produceOutput("\u001B[32mcontrol\u001B[0mseq");
+        assertCharacterPositions(new char[][] { { 'c', 'o', 'n', 't', 'r', 'o', 'l', 's', 'e', 'q' } });
+    }
+
 }