Merge branch 'fix-trace-encoding' into 'master'

Explicitly give Encoding.default_external for trace

Closes #30796

See merge request !10728

changelogs/unreleased/fix-trace-encoding.yml

+---
+title: Fix another case where trace does not have proper encoding set
+merge_request: 10728
+author:

lib/gitlab/ci/trace/stream.rb

@@ -14,6 +14,14 @@ module Gitlab
         def initialize
           @stream = yield
+          if @stream
+            @stream.binmode
+            # Ci::Ansi2html::Converter would read from @stream directly,
+            # using @stream.each_line to be specific. It's safe to set
+            # the encoding here because IO#seek(bytes) and IO#read(bytes)
+            # are not characters based, so encoding doesn't matter to them.
+            @stream.set_encoding(Encoding.default_external)
+          end
         end
         def valid?
@@ -51,7 +59,7 @@ module Gitlab
             read_last_lines(last_lines)
           else
             stream.read
-          end
+          end.force_encoding(Encoding.default_external)
         end
         def html_with_state(state = nil)
@@ -113,7 +121,6 @@ module Gitlab
           end
           chunks.join.lines.last(last_lines).join
-            .force_encoding(Encoding.default_external)
         end
       end
     end

spec/lib/gitlab/ci/trace/stream_spec.rb

@@ -43,13 +43,29 @@ describe Gitlab::Ci::Trace::Stream do
       it 'forwards to the next linefeed, case 1' do
         stream.limit(7)
-        expect(stream.raw).to eq('')
+        result = stream.raw
+
+        expect(result).to eq('')
+        expect(result.encoding).to eq(Encoding.default_external)
       end
       it 'forwards to the next linefeed, case 2' do
         stream.limit(29)
-        expect(stream.raw).to eq("\e[01;32m許功蓋\e[0m\n")
+        result = stream.raw
+
+        expect(result).to eq("\e[01;32m許功蓋\e[0m\n")
+        expect(result.encoding).to eq(Encoding.default_external)
+      end
+
+      # See https://gitlab.com/gitlab-org/gitlab-ce/issues/30796
+      it 'reads in binary, output as Encoding.default_external' do
+        stream.limit(52)
+
+        result = stream.html
+
+        expect(result).to eq("ヾ(´༎ຶД༎ຶ`)ﾉ<br><span class=\"term-fg-green\">許功蓋</span><br>")
+        expect(result.encoding).to eq(Encoding.default_external)
       end
     end
   end