1 files changed, 91 insertions, 0 deletions
diff --git a/vendor/github.com/xo/terminfo/color.go b/vendor/github.com/xo/terminfo/color.go
new file mode 100644
index 000000000..453c29c24
--- /dev/null
+++ b/vendor/github.com/xo/terminfo/color.go
@@ -0,0 +1,91 @@
+package terminfo
+
+import (
+	"os"
+	"strconv"
+	"strings"
+)
+
+// ColorLevel is the color level supported by a terminal.
+type ColorLevel uint
+
+// ColorLevel values.
+const (
+	ColorLevelNone ColorLevel = iota
+	ColorLevelBasic
+	ColorLevelHundreds
+	ColorLevelMillions
+)
+
+// String satisfies the Stringer interface.
+func (c ColorLevel) String() string {
+	switch c {
+	case ColorLevelBasic:
+		return "basic"
+	case ColorLevelHundreds:
+		return "hundreds"
+	case ColorLevelMillions:
+		return "millions"
+	}
+	return "none"
+}
+
+// ChromaFormatterName returns the github.com/alecthomas/chroma compatible
+// formatter name for the color level.
+func (c ColorLevel) ChromaFormatterName() string {
+	switch c {
+	case ColorLevelBasic:
+		return "terminal"
+	case ColorLevelHundreds:
+		return "terminal256"
+	case ColorLevelMillions:
+		return "terminal16m"
+	}
+	return "noop"
+}
+
+// ColorLevelFromEnv returns the color level COLORTERM, FORCE_COLOR,
+// TERM_PROGRAM, or determined from the TERM environment variable.
+func ColorLevelFromEnv() (ColorLevel, error) {
+	// check for overriding environment variables
+	colorTerm, termProg, forceColor := os.Getenv("COLORTERM"), os.Getenv("TERM_PROGRAM"), os.Getenv("FORCE_COLOR")
+	switch {
+	case strings.Contains(colorTerm, "truecolor") || strings.Contains(colorTerm, "24bit") || termProg == "Hyper":
+		return ColorLevelMillions, nil
+	case colorTerm != "" || forceColor != "":
+		return ColorLevelBasic, nil
+	case termProg == "Apple_Terminal":
+		return ColorLevelHundreds, nil
+	case termProg == "iTerm.app":
+		ver := os.Getenv("TERM_PROGRAM_VERSION")
+		if ver == "" {
+			return ColorLevelHundreds, nil
+		}
+		i, err := strconv.Atoi(strings.Split(ver, ".")[0])
+		if err != nil {
+			return ColorLevelNone, ErrInvalidTermProgramVersion
+		}
+		if i == 3 {
+			return ColorLevelMillions, nil
+		}
+		return ColorLevelHundreds, nil
+	}
+
+	// otherwise determine from TERM's max_colors capability
+	if term := os.Getenv("TERM"); term != "" {
+		ti, err := Load(term)
+		if err != nil {
+			return ColorLevelNone, err
+		}
+
+		v, ok := ti.Nums[MaxColors]
+		switch {
+		case !ok || v <= 16:
+			return ColorLevelNone, nil
+		case ok && v >= 256:
+			return ColorLevelHundreds, nil
+		}
+	}
+
+	return ColorLevelBasic, nil
+}