Implement --noColor option.

src/nimblepkg/cli.nim

@@ -19,6 +19,7 @@ type
     level: Priority
     warnings: HashSet[(string, string)]
     suppressionCount: int ## Amount of messages which were not shown.
+    showColor: bool ## Whether messages should be colored.
 
   Priority* = enum
     DebugPriority, LowPriority, MediumPriority, HighPriority
@@ -40,7 +41,8 @@ proc newCLI(): CLI =
   result = CLI(
     level: HighPriority,
     warnings: initSet[(string, string)](),
-    suppressionCount: 0
+    suppressionCount: 0,
+    showColor: true
   )
 
 var globalCLI = newCLI()
@@ -55,11 +57,16 @@ proc displayCategory(category: string, displayType: DisplayType,
   # Calculate how much the `category` must be offset to align along a center
   # line.
   let offset = calculateCategoryOffset(category)
+
   # Display the category.
-  if priority != DebugPriority:
+  let text = "$1$2 " % [spaces(offset), category]
-    setForegroundColor(stdout, foregrounds[displayType])
+  if globalCLI.showColor:
-  writeStyled("$1$2 " % [repeatChar(offset), category], styles[priority])
+    if priority != DebugPriority:
-  resetAttributes()
+      setForegroundColor(stdout, foregrounds[displayType])
+    writeStyled(text, styles[priority])
+    resetAttributes()
+  else:
+    stdout.write(text)
 
 proc displayLine(category, line: string, displayType: DisplayType,
                  priority: Priority) =
@@ -145,6 +152,9 @@ proc promptCustom*(question, default: string): string =
 proc setVerbosity*(level: Priority) =
   globalCLI.level = level
 
+proc setShowColor*(val: bool) =
+  globalCLI.showColor = val
+
 when isMainModule:
   display("Reading", "config file at /Users/dom/.config/nimble/nimble.ini",
           priority = LowPriority)

src/nimblepkg/options.nim

@@ -20,6 +20,7 @@ type
     pkgInfoCache*: TableRef[string, PackageInfo]
     showHelp*: bool
     showVersion*: bool
+    noColor*: bool
 
   ActionType* = enum
     actionNil, actionRefresh, actionInit, actionDump, actionPublish,
@@ -92,6 +93,7 @@ Options:
       --nimbleDir:dirname         Set the Nimble directory.
       --verbose                   Show all non-debug output.
       --debug                     Show all output including debug messages.
+      --noColor                   Don't colorise output.
 
 For more information read the Github readme:
   https://github.com/nim-lang/nimble#readme
@@ -249,6 +251,7 @@ proc parseFlag*(flag, val: string, result: var Options, kind = cmdLongOption) =
   of "nimbledir": result.nimbleDir = val
   of "verbose": result.verbosity = LowPriority
   of "debug": result.verbosity = DebugPriority
+  of "nocolor": result.noColor = true
   # Action-specific flags.
   else:
     case result.action.typ
@@ -318,6 +321,9 @@ proc parseCmdLine*(): Options =
   # Set verbosity level.
   setVerbosity(result.verbosity)
 
+  # Set whether color should be shown.
+  setShowColor(not result.noColor)
+
   # Parse config.
   result.config = parseConfig()