Convert "Invalid source root" errors to UserErrors

src/init.ts

@@ -117,24 +117,7 @@ export async function runInit(
       }
     }
   } catch (e) {
-    // Handle the situation where init is called twice
-    // for the same database in the same job.
-    if (
-      e instanceof Error &&
-      e.message?.includes("Refusing to create databases") &&
-      e.message.includes("exists and is not an empty directory.")
-    ) {
-      throw new util.UserError(
-        `Is the "init" action called twice in the same job? ${e.message}`
-      );
-    } else if (
-      e instanceof Error &&
-      e.message?.includes("is not compatible with this CodeQL CLI")
-    ) {
-      throw new util.UserError(e.message);
-    } else {
-      throw e;
-    }
+    throw processError(e);
   }
   return await getCombinedTracerConfig(
     config,
@@ -144,6 +127,42 @@ export async function runInit(
   );
 }
 
+/**
+ * Possibly convert this error into a UserError in order to avoid
+ * counting this error towards our internal error budget.
+ *
+ * @param e The error to possibly convert to a UserError.
+ *
+ * @returns A UserError if the error is a known error that can be
+ *         attributed to the user, otherwise the original error.
+ */
+function processError(e: any): Error {
+  if (!(e instanceof Error)) {
+    return e;
+  }
+
+  if (
+    // Init action called twice
+    e.message?.includes("Refusing to create databases") &&
+    e.message?.includes("exists and is not an empty directory.")
+  ) {
+    return new util.UserError(
+      `Is the "init" action called twice in the same job? ${e.message}`
+    );
+  }
+
+  if (
+    // Version of CodeQL CLI is incompatible with this version of the CodeQL Action
+    e.message?.includes("is not compatible with this CodeQL CLI") ||
+    // Expected source location for database creation does not exist
+    e.message?.includes("Invalid source root")
+  ) {
+    return new util.UserError(e.message);
+  }
+
+  return e;
+}
+
 // Runs a powershell script to inject the tracer into a parent process
 // so it can tracer future processes, hopefully including the build process.
 // If processName is given then injects into the nearest parent process with