Use exceptions for empty output retries in preparation of related work

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## HEAD
 
 - Add support for GitHub Actions env vars (https://github.com/heroku/hatchet/pull/189)
+- Change HerokuRun#call to use exceptions for empty output retries in preparation of related work
 
 ## 7.4.0
 

lib/hatchet/heroku_run.rb

@@ -48,6 +48,8 @@ def match(value)
   # the command to be empty.
   #
   class HerokuRun
+    class HerokuRunEmptyOutputError < RuntimeError; end
+
     attr_reader :command
 
     def initialize(
@@ -82,22 +84,19 @@ def status
     end
 
     def call
-      loop do
+      begin
         execute!
-
-        break unless output.empty?
-        break unless @retry_on_empty
-
-        @empty_fail_count += 1
-
-        break if @empty_fail_count >= 3
-
-        message = String.new("Empty output from command #{@command}, retrying the command.")
-        message << "\nTo disable pass in `retry_on_empty: false` or set HATCHET_DISABLE_EMPTY_RUN_RETRY=1 globally"
-        message << "\nfailed_count: #{@empty_fail_count}"
-        message << "\nreleases: #{@app.releases}"
-        message << "\n#{caller.join("\n")}"
-        @stderr.puts message
+      rescue HerokuRunEmptyOutputError => e
+        if @retry_on_empty and @empty_fail_count < 3
+          @empty_fail_count += 1
+          message = String.new("Empty output from command #{@command}, retrying the command.")
+          message << "\nTo disable pass in `retry_on_empty: false` or set HATCHET_DISABLE_EMPTY_RUN_RETRY=1 globally"
+          message << "\nfailed_count: #{@empty_fail_count}"
+          message << "\nreleases: #{@app.releases}"
+          message << "\n#{caller.join("\n")}"
+          @stderr.puts message
+          retry
+        end
       end
 
       self
@@ -107,6 +106,7 @@ def call
       ShellThrottle.new(platform_api: @app.platform_api).call do |throttle|
         run_shell!
         throw(:throttle) if @result.stderr.match?(/reached the API rate limit/)
+        raise HerokuRunEmptyOutputError if @result.stdout.empty?
       end
     end