Add emulation-attributes test for true color.

src/tests/Makefile.am

@@ -19,6 +19,7 @@ displaytests = \
 	emulation-attributes-16color.test \
 	emulation-attributes-256color8.test \
 	emulation-attributes-256color248.test \
+	emulation-attributes-truecolor.test \
 	emulation-back-tab.test \
 	emulation-cursor-motion.test \
 	emulation-multiline-scroll.test \

src/tests/emulation-attributes-truecolor.test

@@ -0,0 +1 @@
+emulation-attributes.test

src/tests/emulation-attributes.test

@@ -1,9 +1,10 @@
 #!/bin/sh
 
 #
-# This validates VT100, 16-color, and 256-color attributes against
-# tmux.  It is not run directly, but as subtests based on the
-# executable's name for vt100, 16color, 256color8, and 256color248.
+# This validates VT100, 16-color, 256-color and true color attributes
+# against tmux.  It is not run directly, but as subtests based on the
+# executable's name for vt100, 16color, 256color8, 256color248 and
+# truecolor.
 # This is because Mosh internally represents the first 8 values of the
 # 256color space as though they were the 16-color values they are
 # equivalent to.  tmux does not filter this out on its redisplay, so
@@ -24,6 +25,34 @@ if [ $# -ne 1 ]; then
     fail "bad arguments %s\n" "$@"
 fi
 
+test_true_color()
+{
+    s=$(printf "\033[0")
+    for i in $@; do
+        s="$s;$i"
+    done
+    s="${s}m"
+
+    for attr in $(seq 0 76); do
+        r=$((255-(attr*255/76)))
+        g=$((attr*510/76))
+        b=$((attr*255/76))
+        if [ $g -gt 255 ]; then
+            g=$((510-g))
+        fi
+        invr=$((255-r))
+        invg=$((255-g))
+        invb=$((255-b))
+        c="E"
+
+        printf "%s" "$s"
+        printf "\033[48;2;%d;%d;%dm" $r $g $b;
+        printf "\033[38;2;%d;%d;%dm" $invr $invg $invb
+        printf "%s\033[m" "$c"
+    done
+    printf "\n"
+}
+
 baseline()
 {
     # Strip our name to the last dash-separated word before the .test suffix.
@@ -61,6 +90,26 @@ baseline()
 		printf '\033[48;5;%dmM\033[m ' "$attr"
 	    done
 	    ;;
+        # True color.
+        # See https://gist.github.com/XVilka/8346728 for the test case
+        truecolor)
+            echo "Normal:"
+            test_true_color
+            echo "Bold:"
+            test_true_color 1
+            echo "Italic:"
+            test_true_color 3
+            echo "Underline:"
+            test_true_color 4
+            echo "Blink:"
+            test_true_color 5
+            echo "Inverse:"
+            test_true_color 7
+            echo "Invisible:"
+            test_true_color 8
+            echo "Bold, italic and underline:"
+            test_true_color 1 3 4
+            ;;
 	*)
 	    fail "unknown test name %s\n" "$1"
 	    ;;