Add emacs-compatible report format

src/Psalm/Checker/ProjectChecker.php

@@ -145,6 +145,7 @@ class ProjectChecker
 
     const TYPE_CONSOLE = 'console';
     const TYPE_JSON = 'json';
+    const TYPE_EMACS = 'emacs';
 
     /**
      * @param boolean $use_color
@@ -165,7 +166,7 @@ class ProjectChecker
         $this->debug_output = $debug_output;
         $this->update_docblocks = $update_docblocks;
 
-        if (!in_array($output_format, [self::TYPE_CONSOLE, self::TYPE_JSON])) {
+        if (!in_array($output_format, [self::TYPE_CONSOLE, self::TYPE_JSON, self::TYPE_EMACS])) {
             throw new \UnexpectedValueException('Unrecognised output format ' . $output_format);
         }
 

src/Psalm/CodeLocation.php

@@ -33,6 +33,9 @@ class CodeLocation
     /** @var int */
     protected $selection_end = -1;
 
+    /** @var int */
+    protected $column = -1;
+
     /** @var string */
     protected $snippet = '';
 
@@ -162,6 +165,10 @@ class CodeLocation
         $this->selection_start = max($this->preview_start, $this->selection_start);
         $this->selection_end = min($this->preview_end, $this->selection_end);
 
+        // reset preview start to beginning of line
+        $this->column = $this->selection_start -
+            (int)strrpos($file_contents, "\n", $this->selection_start - strlen($file_contents));
+
         $this->snippet = substr($file_contents, $this->preview_start, $this->preview_end - $this->preview_start);
     }
 
@@ -183,6 +190,16 @@ class CodeLocation
         return $this->snippet;
     }
 
+    /**
+     * @return int
+     */
+    public function getColumn()
+    {
+        $this->calculateRealLocation();
+
+        return $this->column;
+    }
+
     /**
      * @return array<int, int>
      */

src/Psalm/IssueBuffer.php

@@ -79,6 +79,10 @@ class IssueBuffer
                     case ProjectChecker::TYPE_JSON:
                         self::$issue_data[] = self::getIssueArray($e, Config::REPORT_INFO);
                         break;
+
+                    case ProjectChecker::TYPE_EMACS:
+                        echo self::getEmacsOutput($e, Config::REPORT_INFO) . PHP_EOL;
+                        break;
                 }
             }
             return false;
@@ -102,6 +106,10 @@ class IssueBuffer
                 case ProjectChecker::TYPE_JSON:
                     self::$issue_data[] = self::getIssueArray($e);
                     break;
+
+                case ProjectChecker::TYPE_EMACS:
+                    echo self::getEmacsOutput($e) . PHP_EOL;
+                    break;
             }
         }
 
@@ -134,6 +142,20 @@ class IssueBuffer
         ];
     }
 
+    /**
+     * @param  Issue\CodeIssue $e
+     * @param  string          $severity
+     * @return string
+     */
+    protected static function getEmacsOutput(Issue\CodeIssue $e, $severity = Config::REPORT_ERROR)
+    {
+        $location = $e->getLocation();
+        $selection_bounds = $location->getSelectionBounds();
+
+        return $location->file_path . ':' . $location->getLineNumber() . ':' . $location->getColumn() . ': ' .
+            ($severity === Config::REPORT_ERROR ? 'error' : 'warning') . ' - ' . $e->getMessage();
+    }
+
     /**
      * @return array<int, array>
      */