Print file info after source excerpt in diagnostics

Author: mrbdahlem

src/main/java/run/myCode/compiler/CompileDiagnosticListener.java

@@ -50,32 +50,39 @@ private String formatDiagnostic(Diagnostic<? extends JavaFileObject> d) {
         StringBuilder sb = new StringBuilder();
         String sourceName = d.getSource() == null ? "Unknown Source"
                 : new File(d.getSource().getName()).getName();
-        sb.append(sourceName).append(':').append(d.getLineNumber()).append(':')
-                .append(' ').append(d.getKind().toString().toLowerCase(Locale.ENGLISH))
-                .append(':').append(' ').append(d.getMessage(Locale.ENGLISH));
 
+        boolean appendedSource = false;
         try {
             if (d.getSource() != null) {
                 CharSequence content = d.getSource().getCharContent(true);
                 String[] lines = content.toString().split("\r?\n");
                 long lineNo = d.getLineNumber();
                 if (lineNo > 0 && lineNo <= lines.length) {
                     String line = lines[(int) lineNo - 1];
-                    sb.append(System.lineSeparator()).append(line)
-                            .append(System.lineSeparator());
+                    sb.append(line).append(System.lineSeparator());
                     long col = d.getColumnNumber();
                     if (col > 0) {
                         for (int i = 1; i < col; i++) {
                             sb.append(' ');
                         }
                         sb.append('^');
                     }
+                    sb.append(System.lineSeparator());
+                    appendedSource = true;
                 }
             }
         } catch (IOException e) {
             // ignore - if we can't read the source, just return the basic message
         }
 
+        if (!appendedSource && sb.length() > 0) {
+            sb.append(System.lineSeparator());
+        }
+
+        sb.append(sourceName).append(':').append(d.getLineNumber()).append(':')
+                .append(' ').append(d.getKind().toString().toLowerCase(Locale.ENGLISH))
+                .append(':').append(' ').append(d.getMessage(Locale.ENGLISH));
+
         return sb.toString();
     }
 }

src/main/java/zss/compiler/CompileDiagnosticListener.java

@@ -50,32 +50,39 @@ private String formatDiagnostic(Diagnostic<? extends JavaFileObject> d) {
         StringBuilder sb = new StringBuilder();
         String sourceName = d.getSource() == null ? "Unknown Source"
                 : new File(d.getSource().getName()).getName();
-        sb.append(sourceName).append(':').append(d.getLineNumber()).append(':')
-                .append(' ').append(d.getKind().toString().toLowerCase(Locale.ENGLISH))
-                .append(':').append(' ').append(d.getMessage(Locale.ENGLISH));
 
+        boolean appendedSource = false;
         try {
             if (d.getSource() != null) {
                 CharSequence content = d.getSource().getCharContent(true);
                 String[] lines = content.toString().split("\r?\n");
                 long lineNo = d.getLineNumber();
                 if (lineNo > 0 && lineNo <= lines.length) {
                     String line = lines[(int) lineNo - 1];
-                    sb.append(System.lineSeparator()).append(line)
-                            .append(System.lineSeparator());
+                    sb.append(line).append(System.lineSeparator());
                     long col = d.getColumnNumber();
                     if (col > 0) {
                         for (int i = 1; i < col; i++) {
                             sb.append(' ');
                         }
                         sb.append('^');
                     }
+                    sb.append(System.lineSeparator());
+                    appendedSource = true;
                 }
             }
         } catch (IOException e) {
             // ignore - if we can't read the source, just return the basic message
         }
 
+        if (!appendedSource && sb.length() > 0) {
+            sb.append(System.lineSeparator());
+        }
+
+        sb.append(sourceName).append(':').append(d.getLineNumber()).append(':')
+                .append(' ').append(d.getKind().toString().toLowerCase(Locale.ENGLISH))
+                .append(':').append(' ').append(d.getMessage(Locale.ENGLISH));
+
         return sb.toString();
     }
 }

src/test/java/example/HelloFailureTest.java

@@ -32,11 +32,18 @@ public void testCompilationFailureShowsDiagnostics() {
 
         assertFalse("Compiler returned no response", resp == null);
         assertFalse("Compilation unexpectedly succeeded", resp.getSucceeded());
-        assertTrue("Missing file/line in diagnostics", resp.getResult().contains("Broken.java:3"));
-        assertTrue("Missing caret in diagnostics", resp.getResult().contains("^"));
-        assertTrue("Missing source line", resp.getResult().contains("System.out.println(\"hi\")"));
+        String diag = resp.getResult();
+        assertTrue("Missing source line", diag.contains("System.out.println(\"hi\")"));
+        assertTrue("Missing caret in diagnostics", diag.contains("^"));
+        assertTrue("Missing file/line in diagnostics", diag.contains("Broken.java:3"));
 
-        System.out.println("Result: " + resp.getResult());
+        int lineIdx = diag.indexOf("System.out.println(\"hi\")");
+        int caretIdx = diag.indexOf("^");
+        int fileIdx = diag.indexOf("Broken.java:3");
+        assertTrue("Caret should follow source line", lineIdx >= 0 && caretIdx > lineIdx);
+        assertTrue("File info should follow caret", fileIdx > caretIdx);
+
+        System.out.println("Result: " + diag);
     }
 
     private CompileResponse doTest(String resourceName) {