Use updated output with smithy build and diff

Smithy diff and build now uses the pretty validation output and
color theming options.

Because Styles were copied and repated multiple times, I introduced
a ColorTheme class to store reusable styles. This isn't a swappable
color scheme system, but could be evolved into one in the future if
needed.

For Smithy Diff:

The old and new models are both validated, but only build-failing
errors are shown. When the original model fails, a label is added
before ERROR/DANGER to show it's on the OLD model. When the new
model fails, it shows a NEW label.

When running the diff with two valid models, events have a label
of DIFF. The events shown here use the --severity option and default
to WARNING when not set.

For Smithy Build:

Each projection output is contained in a titled section using a
colored title to match whether the projection passed or failed.
Any events encountered during the projection are emitted using the
updated styling and have a prefix label using the projection name.

config/spotbugs/filter.xml

@@ -154,6 +154,10 @@
         <Class name="software.amazon.smithy.cli.commands.WarmupCommand"/>
         <Bug pattern="DM_DEFAULT_ENCODING"/>
     </Match>
+    <Match>
+        <Class name="software.amazon.smithy.cli.DiffCommandTest"/>
+        <Bug pattern="DM_DEFAULT_ENCODING"/>
+    </Match>
 
     <!-- SecurityManager is deprecated and scheduled for removal, so this isn't a good check. -->
     <Match>

smithy-cli/src/it/java/software/amazon/smithy/cli/DiffCommandTest.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package software.amazon.smithy.cli;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.equalTo;
+
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.UncheckedIOException;
+import java.nio.file.Path;
+import org.junit.jupiter.api.Test;
+import software.amazon.smithy.utils.ListUtils;
+
+public class DiffCommandTest {
+    @Test
+    public void passingDiffEventsExitZero() {
+        IntegUtils.withTempDir("diff", dir -> {
+            Path a = dir.resolve("a.smithy");
+            writeFile(a, "$version: \"2.0\"\nnamespace example\nstring A\n");
+
+            RunResult result = IntegUtils.run(dir, ListUtils.of("diff", "--old", a.toString(), "--new", a.toString()));
+            assertThat(result.getExitCode(), equalTo(0));
+        });
+    }
+
+    @Test
+    public void showsLabelForOldModelEvents() {
+        IntegUtils.withTempDir("diff", dir -> {
+            Path a = dir.resolve("a.smithy");
+            writeFile(a, "$version: \"2.0\"\nnamespace example\n@aaaaaa\nstring A\n");
+
+            RunResult result = IntegUtils.run(dir, ListUtils.of("diff", "--old", a.toString(), "--new", a.toString()));
+            assertThat(result.getExitCode(), equalTo(1));
+            assertThat(result.getOutput(), containsString("──  OLD  ERROR  ──"));
+        });
+    }
+
+    @Test
+    public void showsLabelForNewModelEvents() {
+        IntegUtils.withTempDir("diff", dir -> {
+            Path a = dir.resolve("a.smithy");
+            writeFile(a, "$version: \"2.0\"\nnamespace example\nstring A\n");
+
+            Path b = dir.resolve("b.smithy");
+            writeFile(b, "$version: \"2.0\"\nnamespace example\n@aaaaaa\nstring A\n");
+
+            RunResult result = IntegUtils.run(dir, ListUtils.of("diff", "--old", a.toString(), "--new", b.toString()));
+            assertThat(result.getExitCode(), equalTo(1));
+            assertThat(result.getOutput(), containsString("──  NEW  ERROR  ──"));
+        });
+    }
+
+    @Test
+    public void showsLabelForDiffEvents() {
+        IntegUtils.withTempDir("diff", dir -> {
+            Path a = dir.resolve("a.smithy");
+            writeFile(a, "$version: \"2.0\"\nnamespace example\nstring A\n");
+
+            Path b = dir.resolve("b.smithy");
+            writeFile(b, "$version: \"2.0\"\nnamespace example\nstring A\nstring B\n"); // Added B.
+
+            RunResult result = IntegUtils.run(dir, ListUtils.of(
+                    "diff",
+                    "--old", a.toString(),
+                    "--new", b.toString(),
+                    "--severity", "NOTE")); // Note that this is required since the default severity is WARNING.
+            assertThat(result.getExitCode(), equalTo(0));
+            assertThat(result.getOutput(), containsString("──  DIFF  NOTE  ──"));
+        });
+    }
+
+    private void writeFile(Path path, String contents) {
+        try {
+            FileWriter fileWriter = new FileWriter(path.toString());
+            PrintWriter printWriter = new PrintWriter(fileWriter);
+            printWriter.print(contents);
+            printWriter.close();
+        } catch (IOException e) {
+            throw new UncheckedIOException(e);
+        }
+    }
+}

smithy-cli/src/it/java/software/amazon/smithy/cli/IntegUtils.java

@@ -91,7 +91,7 @@ private static List<String> createSmithyCommand(List<String> args) {
         throw new RuntimeException("No SMITHY_BINARY location was set. Did you build the Smithy jlink CLI?");
     }
 
-    private static void withTempDir(String name, Consumer<Path> consumer) {
+    static void withTempDir(String name, Consumer<Path> consumer) {
         try {
             Path path = Files.createTempDirectory(name.replace("/", "_"));
             try {

smithy-cli/src/main/java/software/amazon/smithy/cli/Cli.java

@@ -81,6 +81,8 @@ public int run(String[] args) {
                 Command.Env env = new Command.Env(colorFormatter, stdoutPrinter, stderrPrinter, classLoader);
                 return command.execute(arguments, env);
             } catch (Exception e) {
+                stdoutPrinter.flush();
+                stderrPrinter.flush();
                 printException(e, standardOptions.stackTrace());
                 throw CliError.wrap(e);
             } finally {
@@ -112,13 +114,13 @@ public void stderr(CliPrinter stderrPrinter) {
     private void printException(Throwable e, boolean stacktrace) {
         try (ColorBuffer buffer = ColorBuffer.of(colorFormatter, stderrPrinter)) {
             if (!stacktrace) {
-                colorFormatter.println(stderrPrinter, e.getMessage(), Style.RED);
+                colorFormatter.println(stderrPrinter, e.getMessage(), ColorTheme.ERROR);
             } else {
                 StringWriter writer = new StringWriter();
                 e.printStackTrace(new PrintWriter(writer));
                 String result = writer.toString();
                 int positionOfName = result.indexOf(':');
-                buffer.print(result.substring(0, positionOfName), Style.RED, Style.UNDERLINE);
+                buffer.print(result.substring(0, positionOfName), ColorTheme.ERROR);
                 buffer.println(result.substring(positionOfName));
             }
         }

smithy-cli/src/main/java/software/amazon/smithy/cli/CliPrinter.java

@@ -26,7 +26,6 @@
 /**
  * Handles text output of the CLI.
  */
-@FunctionalInterface
 public interface CliPrinter extends Appendable, Flushable {
 
     @Override
@@ -38,12 +37,7 @@ default CliPrinter append(CharSequence csq) {
     }
 
     @Override
-    default CliPrinter append(CharSequence csq, int start, int end) {
-        for (int i = start; i < end; i++) {
-            append(csq.charAt(i));
-        }
-        return this;
-    }
+    CliPrinter append(CharSequence csq, int start, int end);
 
     /**
      * Prints text to the writer and appends a new line.

smithy-cli/src/main/java/software/amazon/smithy/cli/ColorBuffer.java

@@ -64,9 +64,7 @@ public static ColorBuffer of(ColorFormatter colors, Appendable sink) {
      */
     public static ColorBuffer of(ColorFormatter colors, CliPrinter sink) {
         StringBuilder buffer = new StringBuilder();
-        return new ColorBuffer(colors, buffer, s -> {
-            sink.append(s.toString());
-        });
+        return new ColorBuffer(colors, buffer, s -> sink.append(s.toString()));
     }
 
     @Override

smithy-cli/src/main/java/software/amazon/smithy/cli/ColorTheme.java

@@ -0,0 +1,51 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package software.amazon.smithy.cli;
+
+/**
+ * Standardizes on colors across commands.
+ */
+public final class ColorTheme {
+
+    public static final Style EM_UNDERLINE = Style.of(Style.BRIGHT_WHITE, Style.UNDERLINE);
+    public static final Style DEPRECATED = Style.of(Style.BG_YELLOW, Style.BLACK);
+
+    public static final Style MUTED = Style.of(Style.BRIGHT_BLACK);
+    public static final Style EVENT_SHAPE_ID = Style.of(Style.BRIGHT_MAGENTA);
+    public static final Style LITERAL = Style.of(Style.CYAN);
+
+    public static final Style ERROR_TITLE = Style.of(Style.BG_RED, Style.BLACK);
+    public static final Style ERROR = Style.of(Style.RED);
+
+    public static final Style DANGER_TITLE = Style.of(Style.BG_MAGENTA, Style.BLACK);
+    public static final Style DANGER = Style.of(Style.MAGENTA);
+
+    public static final Style WARNING_TITLE = Style.of(Style.BG_YELLOW, Style.BLACK);
+    public static final Style WARNING = Style.of(Style.YELLOW);
+
+    public static final Style NOTE_TITLE = Style.of(Style.BG_CYAN, Style.BLACK);
+    public static final Style NOTE = Style.of(Style.CYAN);
+
+    public static final Style SUPPRESSED_TITLE = Style.of(Style.BG_GREEN, Style.BLACK);
+    public static final Style SUPPRESSED = Style.of(Style.GREEN);
+
+    public static final Style SUCCESS = Style.of(Style.GREEN);
+
+    public static final Style DIFF_TITLE = Style.of(Style.BG_BRIGHT_BLACK, Style.WHITE);
+    public static final Style DIFF_EVENT_TITLE = Style.of(Style.BG_BRIGHT_BLUE, Style.BLACK);
+
+    private ColorTheme() {}
+}

smithy-cli/src/main/java/software/amazon/smithy/cli/Command.java

@@ -86,6 +86,11 @@ public ClassLoader classLoader() {
             return classLoader == null ? getClass().getClassLoader() : classLoader;
         }
 
+        public void flush() {
+            stderr.flush();
+            stdout.flush();
+        }
+
         public Env withClassLoader(ClassLoader classLoader) {
             return classLoader == this.classLoader ? this : new Env(colors, stdout, stderr, classLoader);
         }

smithy-cli/src/main/java/software/amazon/smithy/cli/HelpPrinter.java

@@ -129,7 +129,7 @@ public void print(ColorFormatter colors, CliPrinter printer) {
         LineWrapper builder = new LineWrapper(maxWidth);
 
         builder.appendWithinLine("Usage: ")
-                .appendWithinLine(colors.style(name, Style.BRIGHT_WHITE, Style.UNDERLINE))
+                .appendWithinLine(colors.style(name, ColorTheme.EM_UNDERLINE))
                 .space();
 
         // Calculate the column manually to account for possible styles interfering with the current column number.
@@ -168,13 +168,13 @@ public void print(ColorFormatter colors, CliPrinter printer) {
 
     private void writeArgHelp(ColorFormatter colors, LineWrapper builder, Arg arg) {
         if (arg.longName != null) {
-            builder.appendWithinLine(colors.style(arg.longName, Style.YELLOW));
+            builder.appendWithinLine(colors.style(arg.longName, ColorTheme.LITERAL));
             if (arg.shortName != null) {
                 builder.appendWithinLine(", ");
             }
         }
         if (arg.shortName != null) {
-            builder.appendWithinLine(colors.style(arg.shortName, Style.YELLOW));
+            builder.appendWithinLine(colors.style(arg.shortName, ColorTheme.LITERAL));
         }
         if (arg.exampleValue != null) {
             builder.space().appendWithinLine(arg.exampleValue);
@@ -213,13 +213,13 @@ String toShortArgs(ColorFormatter colors) {
             StringBuilder builder = new StringBuilder();
             builder.append('[');
             if (longName != null) {
-                builder.append(colors.style(longName, Style.YELLOW));
+                builder.append(colors.style(longName, ColorTheme.LITERAL));
                 if (shortName != null) {
                     builder.append(" | ");
                 }
             }
             if (shortName != null) {
-                builder.append(colors.style(shortName, Style.YELLOW));
+                builder.append(colors.style(shortName, ColorTheme.LITERAL));
             }
             if (exampleValue != null) {
                 builder.append(' ').append(exampleValue);

smithy-cli/src/main/java/software/amazon/smithy/cli/LoggingArgumentsHandler.java

@@ -189,9 +189,9 @@ public void publish(LogRecord record) {
             if (isLoggable(record)) {
                 String formatted = getFormatter().format(record);
                 if (record.getLevel().equals(Level.SEVERE)) {
-                    colors.println(printer, formatted, Style.RED);
+                    colors.println(printer, formatted, ColorTheme.ERROR);
                 } else if (record.getLevel().equals(Level.WARNING)) {
-                    colors.println(printer, formatted, Style.YELLOW);
+                    colors.println(printer, formatted, ColorTheme.WARNING);
                 } else {
                     printer.println(formatted);
                 }

smithy-cli/src/main/java/software/amazon/smithy/cli/Style.java

@@ -15,6 +15,8 @@
 
 package software.amazon.smithy.cli;
 
+import java.util.StringJoiner;
+
 /**
  * Colors and styles for use with {@link AnsiColorFormatter} or {@link CliPrinter}.
  *
@@ -67,15 +69,45 @@ public interface Style {
 
     String getAnsiColorCode();
 
+    static Style of(Style... styles) {
+        if (styles.length == 1) {
+            return styles[0];
+        } else {
+            return new Multi(styles);
+        }
+    }
+
     final class Constant implements Style {
         private final String ansiColorCode;
 
         public Constant(String ansiColorCode) {
             this.ansiColorCode = ansiColorCode;
         }
 
+        @Override
         public String getAnsiColorCode() {
             return ansiColorCode;
         }
     }
+
+    final class Multi implements Style {
+        private final String ansiStyle;
+
+        public Multi(Style... styles) {
+            if (styles.length == 1) {
+                ansiStyle = styles[0].getAnsiColorCode();
+            } else {
+                StringJoiner joiner = new StringJoiner(";");
+                for (Style style : styles) {
+                    joiner.add(style.getAnsiColorCode());
+                }
+                ansiStyle = joiner.toString();
+            }
+        }
+
+        @Override
+        public String getAnsiColorCode() {
+            return ansiStyle;
+        }
+    }
 }