From 4e9eed614123333f00c3e4e2c31565b4e046d9b8 Mon Sep 17 00:00:00 2001
From: Chris Bracken <chris@bracken.jp>
Date: Thu, 20 Dec 2018 11:47:52 -0800
Subject: [PATCH] [License] Enable empty_catches lint

---
 engine/src/flutter/tools/licenses/analysis_options.yaml | 1 +
 engine/src/flutter/tools/licenses/lib/filesystem.dart   | 2 ++
 engine/src/flutter/tools/licenses/lib/licenses.dart     | 6 +++---
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/engine/src/flutter/tools/licenses/analysis_options.yaml b/engine/src/flutter/tools/licenses/analysis_options.yaml
index 2368599d9a..281e646ce2 100644
--- a/engine/src/flutter/tools/licenses/analysis_options.yaml
+++ b/engine/src/flutter/tools/licenses/analysis_options.yaml
@@ -16,6 +16,7 @@ linter:
     - close_sinks
     - control_flow_in_finally
     - empty_statements
+    - empty_catches
     - hash_and_equals
     # - invariant_booleans  # Produces false positives, see https://github.com/flutter/flutter/issues/5790
     - iterable_contains_unrelated_type
diff --git a/engine/src/flutter/tools/licenses/lib/filesystem.dart b/engine/src/flutter/tools/licenses/lib/filesystem.dart
index 60f9d5df60..d11d0d0608 100644
--- a/engine/src/flutter/tools/licenses/lib/filesystem.dart
+++ b/engine/src/flutter/tools/licenses/lib/filesystem.dart
@@ -332,6 +332,8 @@ mixin Latin1TextFile implements TextFile {
         cache(UTF8Of(this), () => utf8.decode(readBytes()));
         isUTF8 = true;
       } on FormatException {
+        // Exceptions are fine/expected for non-UTF8 text, which we test for
+        // immediately below.
       }
       if (isUTF8)
         throw '$fullName contains valid UTF-8 and is probably not actually encoded as Win1252';
diff --git a/engine/src/flutter/tools/licenses/lib/licenses.dart b/engine/src/flutter/tools/licenses/lib/licenses.dart
index 616a498f45..05ce3a3172 100644
--- a/engine/src/flutter/tools/licenses/lib/licenses.dart
+++ b/engine/src/flutter/tools/licenses/lib/licenses.dart
@@ -327,19 +327,19 @@ abstract class License implements Comparable<License> {
     try {
       latin1Encoded = latin1.encode(body);
       isUTF8 = false;
-    } on ArgumentError { }
+    } on ArgumentError { /* Fall through to next encoding check. */ }
     if (!isUTF8) {
       bool isAscii = false;
       try {
         ascii.decode(latin1Encoded);
         isAscii = true;
-      } on FormatException { }
+      } on FormatException { /* Fall through to next encoding check */ }
       if (isAscii)
         return;
       try {
         utf8.decode(latin1Encoded);
         isUTF8 = true;
-      } on FormatException { }
+      } on FormatException { /* We check isUTF8 below and throw if necessary */ }
       if (isUTF8)
         throw 'tried to create a License object with text that appears to have been misdecoded as Latin1 instead of as UTF-8:\n$body';
     }