Fix handling of message beginning on error code line.

Also, add test covering this behavior.

src/diagnostics/iar.ts

@@ -7,7 +7,7 @@ import * as vscode from 'vscode';
 import {oneLess, RawDiagnosticParser, FeedLineResult, RawDiagnostic} from './util';
 
 const CODE_REGEX
-    = /^\"(?<file>.*)\",(?<line>\d+)\s+(?<severity>[A-Za-z]+)\[(?<code>[A-Za-z]+[0-9]+)\]:/;
+    = /^\"(?<file>.*)\",(?<line>\d+)\s+(?<severity>[A-Za-z ]+)\[(?<code>[A-Za-z]+[0-9]+)\]:(?<message_start>.*)$/;
 
 const POINTER_REGEX = /^( +)\^$/;
 
@@ -24,6 +24,7 @@ export class Parser extends RawDiagnosticParser {
   private translateSeverity(iar_severity: string): string {
     switch (iar_severity) {
       case 'Error':
+      case 'Fatal error':
         return 'error';
       case 'Warning':
         return 'warning';
@@ -58,14 +59,14 @@ export class Parser extends RawDiagnosticParser {
           return FeedLineResult.NotMine;
         }
 
-        const [full, file, lineno = '1', severity, code] = mat;
+        const [full, file, lineno = '1', severity, code, message_start] = mat;
         if (file && severity) {
           this.pending_diagnostic = {
             full: full,
             file: file,
             location : new vscode.Range(oneLess(lineno), this.pending_column ?? 0, oneLess(lineno), 999),
             severity: this.translateSeverity(severity),
-            message: "",
+            message: message_start ? message_start + ' ' : '', // Add space ready for the next line of the message. It'll be trimmed if there isn't an additional part to the message.
             code: code,
             related : []
           };
@@ -79,15 +80,12 @@ export class Parser extends RawDiagnosticParser {
         const diagnostic = this.pending_diagnostic!;
 
         if (line === '' || line[0] !== ' ') {
+          diagnostic.message = diagnostic.message.trim();
           this.reset();
           return diagnostic;
         }
 
-        if (diagnostic.message !== '') {
-          diagnostic.message += '\n';
-        }
-
-        diagnostic.message += line.trim();
+        diagnostic.message += line.trim() + '\n';
         diagnostic.full += `\n${line}`;
         return FeedLineResult.Ok;
       }

test/unit-tests/diagnostics.test.ts

@@ -432,4 +432,27 @@ suite('Diagnostics', async () => {
     expect(diagnostic.message).to.eq('identifier "kjfdlkj" is undefined');
     expect(diagnostic.severity).to.eq('error');
   });
+
+  test('Parse IAR fatal error', () => {
+    const lines = [
+      '  #include <kjlkjl>',
+      '                   ^',
+      '"C:\\foo\\bar\\test.c",1  Fatal error[Pe1696]: cannot open source',
+      '          file "kjlkjl"',
+      '            searched: "C:\\Program Files (x86)\\IAR Systems\\Embedded Workbench',
+      '                      8.0\\arm\\inc\\"',
+      '            current directory: "C:\\Users\\user\\Documents"',
+      'Fatal error detected, aborting.'
+    ];
+    feedLines(build_consumer, [], lines);
+    expect(build_consumer.compilers.iar.diagnostics).to.have.length(1);
+    const diagnostic = build_consumer.compilers.iar.diagnostics[0];
+
+    expect(diagnostic.file).to.eq('C:\\foo\\bar\\test.c');
+    expect(diagnostic.location.start.line).to.eq(0);
+    expect(diagnostic.location.start.character).to.eq(17);
+    expect(diagnostic.code).to.eq('Pe1696');
+    expect(diagnostic.message).to.eq('cannot open source file "kjlkjl"\nsearched: "C:\\Program Files (x86)\\IAR Systems\\Embedded Workbench\n8.0\\arm\\inc\\"\ncurrent directory: "C:\\Users\\user\\Documents"');
+    expect(diagnostic.severity).to.eq('error');
+  });
 });