Test for return type of signatures in type documentation

Author: Altai-man

xt/return-type.t

@@ -0,0 +1,26 @@
+use v6;
+use Test;
+use lib 'lib';
+
+my @files;
+
+# Every .pod6 file in the Type directory.
+@files = qx<git ls-files>.lines.grep(* ~~ /'.pod6'/).grep(* ~~ /Type/);
+
+plan +@files;
+
+for @files -> $file {
+    my @lines;
+    my Int $line-no = 1;
+    for $file.IO.lines -> $line {
+        if so $line ~~ /(multi|method|sub) .+? ')' \s+? 'returns' \s+? (<alnum>|':')+? $/ {
+            @lines.push($line-no);
+        }
+        $line-no++;
+    }
+    if @lines {
+        flunk "$file has bad return type at lines: {@lines}";
+    } else {
+        pass "$file return types are ok";
+    }
+}