Count tab as whitespace in "empty shape" check #92

src/shape.c

@@ -201,7 +201,7 @@ int isempty(const sentry_t *shape)
 
 int isdeepempty(const sentry_t *shape)
 /*
- *  Return true if shape is empty, also checking if lines consist of spaces
+ *  Return true if shape is empty, also checking if lines consist of whitespace
  *  only.
  *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
@@ -215,7 +215,7 @@ int isdeepempty(const sentry_t *shape)
 
     for (j = 0; j < shape->height; ++j) {
         if (shape->chars[j]) {
-            if (strspn(shape->chars[j], " ") != shape->width) {
+            if (strspn(shape->chars[j], " \t") != shape->width) {
                 return 0;
             }
         }

test/170_forbid_blank_box.cfg

@@ -0,0 +1,35 @@
+BOX blank1
+
+sample
+    (blank)
+ends
+
+shapes {
+    w (" ")
+}
+
+elastic (
+    w
+)
+
+END blank1
+
+# -------------------------------------------------------
+
+BOX blank2
+
+sample
+    (blank)
+ends
+
+shapes {
+    w (" 	", " 	")    # mix of tabs and spaces
+    e ("   ", "   ")      # space only
+    s ("	", "	")    # tab only
+}
+
+elastic (
+    w, e, s
+)
+
+END blank2

test/170_forbid_blank_box.txt

@@ -0,0 +1,15 @@
+:DESC
+Check that designs which consist only of whitespace are rejected.
+
+:ARGS
+-f 170_forbid_blank_box.cfg -l
+:INPUT
+:OUTPUT-FILTER
+:EXPECTED-ERROR 1
+boxes: 170_forbid_blank_box.cfg: line 9: must specify at least one non-empty shape per design
+boxes: 170_forbid_blank_box.cfg: line 9: skipping to next design
+boxes: 170_forbid_blank_box.cfg: line 29: must specify at least one non-empty shape per design
+boxes: 170_forbid_blank_box.cfg: line 29: skipping to next design
+boxes: no valid data in config file -- 170_forbid_blank_box.cfg
+boxes: no valid designs found
+:EOF