--no-color flag doesn't suppress color output

[veelenga]

I tried 3 cases:

1. crystal eval:

$ crystal eval --no-color                                                                                                                                                             
require "colorize"
puts "hello".colorize(:red)
hello #=> colorized output

2. crystal run:

$ cat test.cr                                                                                                                                                                          
require "colorize"
puts "hello".colorize(:red)

$ crystal test.cr --no-color                                                                                                                                                           
hello #=> colorized output

3. crystal spec:

 $ crystal spec spec/std/bool_spec.cr --no-color                                                                                                                                        
....................  #=> colorized output

Finished in 830 microseconds
20 examples, 0 failures, 0 errors, 0 pending #=> colorized output

I expect the output colors to be suppressed in each of those cases.

Crystal 0.21.1+70 [7ca33b9] (2017-04-14) LLVM 4.0.0 on OS X 10.12

[bew]

The --no-color flag disable formatting (color, bold,..) in the compiler, not in the executed program.
For example, a compilation error with --no-color won't be in bold.

[veelenga]

@bew ok, that's not really intuitive at the first glance but makes sense:

$ crystal eval                                                                                                                                                                   
puts a
Error in line 1: undefined local variable or method 'a' (did you mean 'p'?) # => colorized

$ crystal eval --no-color                                                                                                                                                              
puts a
Error in line 1: undefined local variable or method 'a' (did you mean 'p'?) # => not colorized

What about spec output (case 3) ? #1587

[bew]

About the spec output, the mentioned patch seems to be gone now..

Maybe we could add an ENV variable SPEC_NO_COLOR when --no-color is specified, so the compiled specs can disable colors at compile-time

[bew]

something like this for example:

diff --git a/src/compiler/crystal/command/spec.cr b/src/compiler/crystal/command/spec.cr
index 49f1803df..b87849d4c 100644
--- a/src/compiler/crystal/command/spec.cr
+++ b/src/compiler/crystal/command/spec.cr
@@ -60,6 +60,10 @@ class Crystal::Command
       end
     end
 
+    if @color
+      compiler.flags << "SPEC_NO_COLOR"
+    end
+
     source_filename = File.expand_path("spec")
 
     source = target_filenames.map { |filename| %(require "./#{filename}") }.join("\n")
diff --git a/src/spec.cr b/src/spec.cr
index cbc605a6c..d08539686 100644
--- a/src/spec.cr
+++ b/src/spec.cr
@@ -113,6 +113,10 @@ if ENV["SPEC_VERBOSE"]? == "1"
   Spec.override_default_formatter(Spec::VerboseFormatter.new)
 end
 
+{% if flag?("SPEC_NO_COLOR") %}
+  Spec.use_colors = false
+{% end %}
+
 Signal::INT.trap { Spec.abort! }
 
 Spec.run

[ysbaddaden]

Couldn't the crystal spec command accept --no-color, or pass it along?

[luislavena]

You can pass --no-color to the compiled spec and it will partially disable coloring.

The option is not accepted or passed by to the child program by crystal spec (or displayed at all):

$ cat 48.cr 
require "spec"

$ crystal spec 48.cr -- --help
crystal spec runner
    -e , --example STRING            run examples whose full nested names include STRING
    -l , --line LINE                 run examples whose line matches LINE
    -p, --profile                    Print the 10 slowest specs
    --fail-fast                      abort the run on first failure
    --location file:line             run example at line 'line' in file 'file', multiple allowed
    --junit_output OUTPUT_DIR        generate JUnit XML output
    --help                           show this help
    -v, --verbose                    verbose output
    --no-color                       Disable colored output

$ cat 50.cr 
require "spec"

describe "Something" do
  it "fails" do
    true.should be_false
  end
end

$ crystal spec 50.cr -- --no-color
Using compiled compiler at .build/crystal
F

Failures:

  1) Something fails
     Failure/Error: true.should be_false

       Expected: false
            got: true

     # 50.cr:5

Finished in 96 microseconds
1 examples, 1 failures, 0 errors, 0 pending

Failed examples:

crystal spec 50.cr:4 # Something fails

And even so contains colored elements:

Versus full colored one:

[veelenga]

Thx @luislavena