diff --git a/lib/gears/color.lua b/lib/gears/color.lua index c8c1f2ba..bf8664b2 100644 --- a/lib/gears/color.lua +++ b/lib/gears/color.lua @@ -22,51 +22,50 @@ local pattern_cache --- Parse a HTML-color. -- This function can parse colors like `#rrggbb` and `#rrggbbaa` and also `red`. --- Thanks to #lua for this. :) +-- Max 4 chars per channel. Thanks to #lua for this. :) -- -- @param col The color to parse --- @return 4 values which each are in the range [0, 1]. +-- @return 4 values representing color in RGBA format (each of them in [0, 1] +-- range) or nil if input is incorrect. -- @usage -- This will return 0, 1, 0, 1 -- gears.color.parse_color("#00ff00ff") function color.parse_color(col) local rgb = {} - -- Is it a HTML-style color? if string.match(col, "^#%x+$") then - -- Get all hex chars - for char in string.gmatch(col, "[^#]") do - table.insert(rgb, tonumber(char, 16) / 0xf) + local hex_str = col:sub(2, #col) + local channels + if #hex_str % 3 == 0 then + channels = 3 + elseif #hex_str % 4 == 0 then + channels = 4 + else + return nil end - -- Merge consecutive values until we have at most four groups (rgba) - local factor = 0xf - while #rgb > 4 do - local merged = {} - local key, value = next(rgb, nil) - local next_factor = (factor + 1)*(factor + 1) - 1 - while key do - local key2, value2 = next(rgb, key) - local v1, v2 = value * factor, value2 * factor - local new = v1 * (factor + 1) + v2 - table.insert(merged, new / next_factor) - key, value = next(rgb, key2) - end - rgb = merged - factor = next_factor + local chars_per_channel = #hex_str / channels + if chars_per_channel > 4 then + return nil + end + local dividor = 0x10^chars_per_channel - 1 + for idx=1,#hex_str,chars_per_channel do + local channel_val = tonumber(hex_str:sub(idx,idx+chars_per_channel-1), 16) + table.insert(rgb, channel_val / dividor) + end + if channels == 3 then + table.insert(rgb, 1) end else - -- Let's ask Pango for its opinion (but this doesn't support alpha!) local c = Pango.Color() - if c:parse(col) then - rgb = { - c.red / 0xffff, - c.green / 0xffff, - c.blue / 0xffff, - } + if not c:parse(col) then + return nil end + rgb = { + c.red / 0xffff, + c.green / 0xffff, + c.blue / 0xffff, + 1.0 + } end - -- Add missing groups (missing alpha) - while #rgb < 4 do - table.insert(rgb, 1) - end + assert(#rgb == 4, col) return unpack(rgb) end diff --git a/spec/gears/color_spec.lua b/spec/gears/color_spec.lua index 47b157ca..2ac33eab 100644 --- a/spec/gears/color_spec.lua +++ b/spec/gears/color_spec.lua @@ -42,6 +42,26 @@ describe("gears.color", function() test(0x7f, 0xff, 0x00, 0xff, "chartreuse") end) + describe("invalid input", function() + local function test_nil(input) + local output = color.parse_color(input) + assert.is_nil(output) + end + + it("nonexisting color", function() + test_nil("elephant") + end) + + it("invalid format", function() + test_nil('#f0f0f') + end) + + it("too long", function() + test_nil("#00000fffff00000fffff") + end) + end) + + describe("different lengths", function() local function gray(e, e_a, input) local o_r, o_g, o_b, o_a, unused = color.parse_color(input)