[#237] Modify coloring options

CHANGES.md

@@ -49,6 +49,9 @@ Unreleased
     configuration file with the `externalRefRedirects` parameter.
 * [#261](https://github.com/serokell/xrefcheck/pull/261)
   + Symlinks are now not processed by the scanner.
+* [#268](https://github.com/serokell/xrefcheck/pull/268)
+  + Added CLI option `--color` that enables ANSI colors in output.
+  + Changed the output coloring defaults to show colors when `CI` env variable is `true`.
 
 0.2.2
 ==========

src/Xrefcheck/CLI.hs

@@ -83,7 +83,7 @@ data Options = Options
   , oMode              :: VerifyMode
   , oVerbose           :: Bool
   , oShowProgressBar   :: Maybe Bool
-  , oColorMode         :: ColorMode
+  , oColorMode         :: Maybe ColorMode
   , oExclusionOptions  :: ExclusionOptions
   , oNetworkingOptions :: NetworkingOptions
   , oScanPolicy        :: ScanPolicy
@@ -185,9 +185,17 @@ optionsParser = do
         help "Do not display progress bar during verification."
     , pure Nothing
     ]
-  oColorMode <- flag WithColors WithoutColors $
-    long "no-color" <>
-    help "Disable ANSI coloring of output."
+  oColorMode <- asum
+    [ flag' (Just WithColors) $
+        long "color" <>
+        help "Enable ANSI coloring of output. \
+            \When `CI` env var is set to true or the command output corresponds to a terminal, \
+            \this option will be enabled by default."
+    , flag' (Just WithoutColors) $
+        long "no-color" <>
+        help "Disable ANSI coloring of output."
+    , pure Nothing
+    ]
   oExclusionOptions <- exclusionOptionsParser
   oNetworkingOptions <- networkingOptionsParser
   oScanPolicy <- flag OnlyTracked IncludeUntracked $

src/Xrefcheck/Command.hs

@@ -48,8 +48,14 @@ findFirstExistingFile = \case
 
 defaultAction :: Options -> IO ()
 defaultAction Options{..} = do
+  withinCI <- askWithinCI
   coloringSupported <- supportsPretty
-  give (if coloringSupported then oColorMode else WithoutColors) $ do
+  let colorMode = oColorMode ?:
+        if withinCI || coloringSupported
+        then WithColors
+        else WithoutColors
+
+  give colorMode $ do
     config <- case oConfigPath of
       Just configPath -> readConfig configPath
       Nothing -> do
@@ -64,7 +70,6 @@ defaultAction Options{..} = do
               |]
             pure $ defConfig GitHub
 
-    withinCI <- askWithinCI
     let showProgressBar = oShowProgressBar ?: not withinCI
 
     (ScanResult scanErrs repoInfo) <- allowRewrite showProgressBar $ \rw -> do

tests/golden/check-color/check-color.bats

@@ -0,0 +1,34 @@
+#!/usr/bin/env bats
+
+# SPDX-FileCopyrightText: 2023 Serokell <https://serokell.io>
+#
+# SPDX-License-Identifier: MPL-2.0
+
+load '../helpers/bats-support/load'
+load '../helpers/bats-assert/load'
+load '../helpers/bats-file/load'
+load '../helpers'
+
+# The CI variable must be always explicitly set in these tests because they are checking for an
+# intended behavior regardless of where they are actually being run (e.g. "No color flag (not
+# in CI)") may be running in CI).
+
+@test "Color flag (not in CI)" {
+  CI=false xrefcheck -v --no-progress --color | diff - expected-color.gold
+}
+
+@test "No color flag (not in CI)" {
+  CI=false xrefcheck -v --no-progress --no-color | diff - expected-no-color.gold
+}
+
+@test "No color default when pipe (not in CI)" {
+  CI=false xrefcheck -v --no-progress | diff - expected-no-color.gold
+}
+
+@test "Color default when CI" {
+  CI=true xrefcheck -v --no-progress | diff - expected-color.gold
+}
+
+@test "No color flag in CI" {
+  CI=true xrefcheck -v --no-progress --no-color | diff - expected-no-color.gold
+}

tests/golden/check-color/color.md

@@ -0,0 +1,9 @@
+<!--
+ - SPDX-FileCopyrightText: 2023 Serokell <https://serokell.io>
+ -
+ - SPDX-License-Identifier: MPL-2.0
+ -->
+
+# Color
+
+[Color](#Color)

tests/golden/check-color/expected-color.gold

@@ -0,0 +1,12 @@
+=== Repository data ===
+
+  color.md:
+    - references:
+        - reference (file-local) at src:9:1-15:
+            - text: "Color"
+            - link: -
+            - anchor: Color
+    - anchors:
+        - color (header I) at src:7:1-7
+
+All repository links are valid.

tests/golden/check-color/expected-no-color.gold

@@ -0,0 +1,12 @@
+=== Repository data ===
+
+  color.md:
+    - references:
+        - reference (file-local) at src:9:1-15:
+            - text: "Color"
+            - link: -
+            - anchor: Color
+    - anchors:
+        - color (header I) at src:7:1-7
+
+All repository links are valid.