support Ruby 2.4

For td-agent v3.1.1 and later.
(Embedded Fluentd version must be v1)

Signed-off-by: Daijiro Fukuda <fukuda@clear-code.com>

Author: daipom

.github/workflows/main.yml

@@ -15,9 +15,13 @@ jobs:
         os: [ubuntu-latest, macos-latest, windows-latest]
         include:
           - os: ubuntu-latest
-            ruby: 2.7.1
+            ruby: '2.7.1'
+          - os: ubuntu-latest
+            ruby: '2.4.2'
+          - os: windows-latest
+            ruby: '2.7.1'
           - os: windows-latest
-            ruby: 2.7.1
+            ruby: '2.4.2'
     runs-on: ${{ matrix.os }}
     name: Test with Ruby ${{ matrix.ruby }} on ${{ matrix.os }}
     steps:
@@ -58,6 +62,8 @@ jobs:
             shell: bash
           - os: windows-latest
             shell: cmd
+          - ruby: '2.7.1'
+            fluentd: '1.11.1'
     runs-on: ${{ matrix.os }}
     name: Gem test with Ruby ${{ matrix.ruby }} on ${{ matrix.os }}
     steps:
@@ -69,6 +75,9 @@ jobs:
         with:
           name: gem
           path: pkg
+      - name: Install specific version Fluentd
+        if: ${{ matrix.fluentd != '' }}
+        run: gem install fluentd --version ${{ matrix.fluentd }}
       - name: Install gem
         run: gem install pkg/*
       - name: Test command (bash)

lib/fluent/tail_checker/collection_ratio_checker.rb

@@ -50,7 +50,7 @@ def check
           ratio = collection_ratio(entry.pos, size)
           if ratio < @collection_ratio_threshold
             unacceptable_collection_ratio_found = true
-            unacceptable_collection_ratio_path_and_ratio_list.append([entry.path, ratio])
+            unacceptable_collection_ratio_path_and_ratio_list.push([entry.path, ratio])
           end
         end
 

lib/fluent/tail_checker/pos.rb

@@ -50,7 +50,7 @@ def self.load_entries(path)
       end
 
       def watching_entries
-        entries.filter do |entry|
+        entries.select do |entry|
           not entry.unwatched?
         end
       end