Merge pull request #110 from airbrake/cause-1-9-3-fix

backtrace: fix ExecJS backtraces support for Ruby 1.9.3

CHANGELOG.md

@@ -3,6 +3,9 @@ Airbrake Ruby Changelog
 
 ### master
 
+* Fixed support for ExecJS backtraces for Ruby 1.9.3 sometimes resulting in
+  `NameError` ([#110](https://github.com/airbrake/airbrake-ruby/pull/110))
+
 ### [v1.4.5][v1.4.5] (August 15, 2016)
 
 * Added support for CoffeeScript/ExecJS backtraces

lib/airbrake-ruby.rb

@@ -63,6 +63,11 @@ module Airbrake
   # @return [String] the label to be prepended to the log output
   LOG_LABEL = '**Airbrake:'.freeze
 
+  ##
+  # @return [Boolean] true if current Ruby is Ruby 1.9.*. The result is used
+  #   for special cases where we need to work around older implementations
+  RUBY_19 = RUBY_VERSION.start_with?('1.9')
+
   ##
   # A Hash that holds all notifiers. The keys of the Hash are notifier
   # names, the values are Airbrake::Notifier instances.

lib/airbrake-ruby/backtrace.rb

@@ -11,74 +11,81 @@ module Airbrake
   #     Backtrace.parse($!, Logger.new(STDOUT))
   #   end
   module Backtrace
-    ##
-    # @return [Regexp] the pattern that matches standard Ruby stack frames,
-    #   such as ./spec/notice_spec.rb:43:in `block (3 levels) in <top (required)>'
-    RUBY_STACKFRAME_REGEXP = %r{\A
-      (?<file>.+)       # Matches './spec/notice_spec.rb'
-      :
-      (?<line>\d+)      # Matches '43'
-      :in\s
-      `(?<function>.*)' # Matches "`block (3 levels) in <top (required)>'"
-    \z}x
-
-    ##
-    # @return [Regexp] the template that matches JRuby Java stack frames, such
-    #  as org.jruby.ast.NewlineNode.interpret(NewlineNode.java:105)
-    JAVA_STACKFRAME_REGEXP = /\A
-      (?<function>.+)  # Matches 'org.jruby.ast.NewlineNode.interpret
-      \(
-        (?<file>[^:]+) # Matches 'NewlineNode.java'
-        :?
-        (?<line>\d+)?  # Matches '105'
-      \)
-    \z/x
-
-    ##
-    # @return [Regexp] the template that tries to assume what a generic stack
-    #   frame might look like, when exception's backtrace is set manually.
-    GENERIC_STACKFRAME_REGEXP = %r{\A
-      (?:from\s)?
-      (?<file>.+)              # Matches '/foo/bar/baz.ext'
-      :
-      (?<line>\d+)?            # Matches '43' or nothing
-      (?:
-        in\s`(?<function>.+)'  # Matches "in `func'"
-      |
-        :in\s(?<function>.+)   # Matches ":in func"
-      )?                       # ... or nothing
-    \z}x
-
-    ##
-    # @return [Regexp] the template that matches exceptions from PL/SQL such as
-    #   ORA-06512: at "STORE.LI_LICENSES_PACK", line 1945
-    # @note This is raised by https://github.com/kubo/ruby-oci8
-    OCI_STACKFRAME_REGEXP = /\A
-      (?:
-        ORA-\d{5}
-        :\sat\s
-        (?:"(?<function>.+)",\s)?
-        line\s(?<line>\d+)
-      |
-        #{GENERIC_STACKFRAME_REGEXP}
-      )
-    \z/x
-
-    ##
-    # @return [Regexp] the template that matches CoffeeScript backtraces
-    #   usually coming from Rails & ExecJS
-    EXECJS_STACKFRAME_REGEXP = /\A
-      (?:
-        # Matches 'compile ((execjs):6692:19)'
-        (?<function>.+)\s\((?<file>.+):(?<line>\d+):\d+\)
-      |
-        # Matches 'bootstrap_node.js:467:3'
-        (?<file>.+):(?<line>\d+):\d+(?<function>)
-      |
-        # Matches the Ruby part of the backtrace
-        #{RUBY_STACKFRAME_REGEXP}
-      )
-    \z/x
+    module Patterns
+      ##
+      # @return [Regexp] the pattern that matches standard Ruby stack frames,
+      #   such as ./spec/notice_spec.rb:43:in `block (3 levels) in <top (required)>'
+      RUBY = %r{\A
+        (?<file>.+)       # Matches './spec/notice_spec.rb'
+        :
+        (?<line>\d+)      # Matches '43'
+        :in\s
+        `(?<function>.*)' # Matches "`block (3 levels) in <top (required)>'"
+      \z}x
+
+      ##
+      # @return [Regexp] the pattern that matches JRuby Java stack frames, such
+      #  as org.jruby.ast.NewlineNode.interpret(NewlineNode.java:105)
+      JAVA = /\A
+        (?<function>.+)  # Matches 'org.jruby.ast.NewlineNode.interpret
+        \(
+          (?<file>[^:]+) # Matches 'NewlineNode.java'
+          :?
+          (?<line>\d+)?  # Matches '105'
+        \)
+      \z/x
+
+      ##
+      # @return [Regexp] the pattern that tries to assume what a generic stack
+      #   frame might look like, when exception's backtrace is set manually.
+      GENERIC = %r{\A
+        (?:from\s)?
+        (?<file>.+)              # Matches '/foo/bar/baz.ext'
+        :
+        (?<line>\d+)?            # Matches '43' or nothing
+        (?:
+          in\s`(?<function>.+)'  # Matches "in `func'"
+        |
+          :in\s(?<function>.+)   # Matches ":in func"
+        )?                       # ... or nothing
+      \z}x
+
+      ##
+      # @return [Regexp] the pattern that matches exceptions from PL/SQL such as
+      #   ORA-06512: at "STORE.LI_LICENSES_PACK", line 1945
+      # @note This is raised by https://github.com/kubo/ruby-oci8
+      OCI = /\A
+        (?:
+          ORA-\d{5}
+          :\sat\s
+          (?:"(?<function>.+)",\s)?
+          line\s(?<line>\d+)
+        |
+          #{GENERIC}
+        )
+      \z/x
+
+      ##
+      # @return [Regexp] the pattern that matches CoffeeScript backtraces
+      #   usually coming from Rails & ExecJS
+      EXECJS = /\A
+        (?:
+          # Matches 'compile ((execjs):6692:19)'
+          (?<function>.+)\s\((?<file>.+):(?<line>\d+):\d+\)
+        |
+          # Matches 'bootstrap_node.js:467:3'
+          (?<file>.+):(?<line>\d+):\d+(?<function>)
+        |
+          # Matches the Ruby part of the backtrace
+          #{RUBY}
+        )
+      \z/x
+
+      ##
+      # @return [Regexp] +EXECJS+ pattern without named captures and
+      #   uncommon frames
+      EXECJS_SIMPLIFIED = /\A.+ \(.+:\d+:\d+\)\z/
+    end
 
     ##
     # Parses an exception's backtrace.
@@ -121,27 +128,38 @@ class << self
 
       def best_regexp_for(exception)
         if java_exception?(exception)
-          JAVA_STACKFRAME_REGEXP
+          Patterns::JAVA
         elsif oci_exception?(exception)
-          OCI_STACKFRAME_REGEXP
+          Patterns::OCI
         elsif execjs_exception?(exception)
-          EXECJS_STACKFRAME_REGEXP
+          Patterns::EXECJS
         else
-          RUBY_STACKFRAME_REGEXP
+          Patterns::RUBY
         end
       end
 
       def oci_exception?(exception)
         defined?(OCIError) && exception.is_a?(OCIError)
       end
 
+      # rubocop:disable Metrics/PerceivedComplexity, Metrics/CyclomaticComplexity
       def execjs_exception?(exception)
         return false unless defined?(ExecJS::RuntimeError)
         return true if exception.is_a?(ExecJS::RuntimeError)
-        return true if exception.cause && exception.cause.is_a?(ExecJS::RuntimeError)
+
+        if Airbrake::RUBY_19
+          # Ruby 1.9 doesn't support Exception#cause. We work around this by
+          # parsing backtraces. It's slow, so we check only a few first frames.
+          exception.backtrace[0..2].each do |frame|
+            return true if frame =~ Patterns::EXECJS_SIMPLIFIED
+          end
+        elsif exception.cause && exception.cause.is_a?(ExecJS::RuntimeError)
+          return true
+        end
 
         false
       end
+      # rubocop:enable Metrics/PerceivedComplexity, Metrics/CyclomaticComplexity
 
       def stack_frame(match)
         { file: match[:file],
@@ -153,7 +171,7 @@ def match_frame(regexp, stackframe)
         match = regexp.match(stackframe)
         return match if match
 
-        GENERIC_STACKFRAME_REGEXP.match(stackframe)
+        Patterns::GENERIC.match(stackframe)
       end
     end
   end

spec/backtrace_spec.rb

@@ -191,7 +191,7 @@
       end
     end
 
-    context "given an ExecJS backtrace" do
+    context "given an ExecJS exception" do
       let(:bt) do
         ['compile ((execjs):6692:19)',
          'eval (<anonymous>:1:10)',
@@ -203,8 +203,6 @@
          "/opt/rubies/ruby-2.3.1/lib/ruby/2.3.0/benchmark.rb:308:in `realtime'"]
       end
 
-      let(:ex) { ExecJS::RuntimeError.new.tap { |e| e.set_backtrace(bt) } }
-
       let(:parsed_backtrace) do
         [{ file: '(execjs)', line: 6692, function: 'compile' },
          { file: '<anonymous>', line: 1, function: 'eval' },
@@ -218,11 +216,35 @@
            function: 'realtime' }]
       end
 
-      it "returns a properly formatted array of hashes" do
-        stub_const('ExecJS::RuntimeError', AirbrakeTestError)
-        expect(
-          described_class.parse(ex, Logger.new('/dev/null'))
-        ).to eq(parsed_backtrace)
+      context "when not on Ruby 1.9" do
+        let(:ex) { ExecJS::RuntimeError.new.tap { |e| e.set_backtrace(bt) } }
+
+        it "returns a properly formatted array of hashes" do
+          stub_const('ExecJS::RuntimeError', AirbrakeTestError)
+          stub_const('Airbrake::RUBY_19', false)
+
+          expect(
+            described_class.parse(ex, Logger.new('/dev/null'))
+          ).to eq(parsed_backtrace)
+        end
+      end
+
+      context "when on Ruby 1.9" do
+        context "and when exception's class isn't ExecJS" do
+          let(:ex) do
+            ActionView::Template::Error.new.tap { |e| e.set_backtrace(bt) }
+          end
+
+          it "returns a properly formatted array of hashes" do
+            stub_const('ActionView::Template::Error', AirbrakeTestError)
+            stub_const('ExecJS::RuntimeError', NameError)
+            stub_const('Airbrake::RUBY_19', true)
+
+            expect(
+              described_class.parse(ex, Logger.new('/dev/null'))
+            ).to eq(parsed_backtrace)
+          end
+        end
       end
     end
   end