forth: String word set COMPARE/SEARCH/SLITERAL (+9)

lib/forth/tests/test-phase5.sx

@@ -268,6 +268,38 @@
       "S\" /tmp/nope.fxf\" R/O OPEN-FILE SWAP DROP 0 ="
       0)))
 
+(define
+  forth-p5-string-tests
+  (fn
+    ()
+    (forth-p5-check-top "COMPARE equal" "S\" ABC\" S\" ABC\" COMPARE" 0)
+    (forth-p5-check-top "COMPARE less" "S\" ABC\" S\" ABD\" COMPARE" -1)
+    (forth-p5-check-top "COMPARE greater" "S\" ABD\" S\" ABC\" COMPARE" 1)
+    (forth-p5-check-top
+      "COMPARE prefix less"
+      "S\" AB\" S\" ABC\" COMPARE"
+      -1)
+    (forth-p5-check-top
+      "COMPARE prefix greater"
+      "S\" ABC\" S\" AB\" COMPARE"
+      1)
+    (forth-p5-check-top
+      "SEARCH found flag"
+      "S\" HELLO WORLD\" S\" WORLD\" SEARCH"
+      -1)
+    (forth-p5-check-top
+      "SEARCH not found flag"
+      "S\" HELLO\" S\" XYZ\" SEARCH"
+      0)
+    (forth-p5-check-top
+      "SEARCH empty needle flag"
+      "S\" HELLO\" S\" \" SEARCH"
+      -1)
+    (forth-p5-check-top
+      "SLITERAL via [ S\" ... \" ]"
+      ": A [ S\" HI\" ] SLITERAL ; A SWAP DROP"
+      2)))
+
 (define
   forth-p4-check-output-passthrough
   (fn
@@ -291,6 +323,7 @@
     (forth-p5-state-tests)
     (forth-p5-misc-tests)
     (forth-p5-fa-tests)
+    (forth-p5-string-tests)
     (dict
       "passed"
       forth-p5-passed