Kotlin: Add total number of diagnostics to telemetry

Author: igfoo

java/kotlin-extractor/src/main/kotlin/utils/Logger.kt

@@ -138,6 +138,10 @@ open class LoggerBase(val logCounter: LogCounter) {
         fullMsgBuilder.append(suffix)
 
         val fullMsg = fullMsgBuilder.toString()
+        emitDiagnostic(tw, severity, diagnosticLocStr, msg, fullMsg, locationString, mkLocationId)
+    }
+
+    fun emitDiagnostic(tw: TrapWriter, severity: Severity, diagnosticLocStr: String, msg: String, fullMsg: String, locationString: String? = null, mkLocationId: () -> Label<DbLocation> = { tw.unknownLocation }) {
         val locStr = if (locationString == null) "" else "At " + locationString + ": "
         val kind = if (severity <= Severity.WarnHigh) "WARN" else "ERROR"
         val logMessage = LogMessage(kind, "Diagnostic($diagnosticLocStr): $locStr$fullMsg")
@@ -190,9 +194,10 @@ open class LoggerBase(val logCounter: LogCounter) {
                 // We don't know if this location relates to an error
                 // or a warning, so we just declare hitting the limit
                 // to be an error regardless.
-                val logMessage = LogMessage("ERROR", "Total of $count diagnostics from $caller.")
-                tw.writeComment(logMessage.toText())
-                logStream.write(logMessage.toJsonLine())
+                val message = "Total of $count diagnostics (reached limit of ${logCounter.diagnosticLimit}) from $caller."
+                if (verbosity >= 1) {
+                    emitDiagnostic(tw, Severity.Error, "Limit", message, message)
+                }
             }
         }
     }

java/ql/src/Telemetry/ExtractorInformation.ql

@@ -53,6 +53,34 @@ predicate extractorDiagnostics(string key, int value) {
   )
 }
 
+/*
+ * Just counting the diagnostics doesn't give the full picture, as
+ * CODEQL_EXTRACTOR_KOTLIN_DIAGNOSTIC_LIMIT means that some diagnostics
+ * will be suppressed. In that case, we need to look for the
+ * suppression message, uncount those that did get emitted, uncount the
+ * suppression message itself, and then add on the full count.
+ */
+
+predicate extractorTotalDiagnostics(string key, int value) {
+  exists(string extractor |
+    key = "Total number of diagnostics from " + extractor and
+    value =
+      strictcount(Diagnostic d | d.getGeneratedBy() = extractor) +
+        sum(Diagnostic d |
+          d.getGeneratedBy() = extractor
+        |
+          d.getMessage()
+                  .regexpCapture("Total of ([0-9]+) diagnostics \\(reached limit of ([0-9]+)\\).*",
+                    1)
+                  .toInt() -
+              d.getMessage()
+                  .regexpCapture("Total of ([0-9]+) diagnostics \\(reached limit of ([0-9]+)\\).*",
+                    2)
+                  .toInt() - 1
+        )
+  )
+}
+
 from string key, int value
 where
   fileCount(key, value) or
@@ -61,5 +89,6 @@ where
   numberOfLinesOfCode(key, value) or
   totalNumberOfLinesByExtension(key, value) or
   numberOfLinesOfCodeByExtension(key, value) or
-  extractorDiagnostics(key, value)
+  extractorDiagnostics(key, value) or
+  extractorTotalDiagnostics(key, value)
 select key, value