more friendly error message when renaming patterns

testsuite/compiler/renamer/funpatt.gf

@@ -0,0 +1,14 @@
+abstract funpatt = {
+
+-- this should raise error
+-- we cannot pattern match on functions
+
+cat D ;
+fun D1 : D ;
+    D2 : D ;
+
+fun d : D -> Int ;
+def d D1 = 1 ;
+    d D2 = 2 ;
+
+}

testsuite/compiler/renamer/funpatt.gfs

@@ -0,0 +1 @@
+i -src testsuite/compiler/renamer/funpatt.gf

testsuite/compiler/renamer/funpatt.gfs.gold

@@ -0,0 +1,7 @@
+␍
+␍
+data constructor expected but funpatt.D1 is found instead␍
+OCCURRED IN␍
+renaming definition of d in funpatt.gf, line 12␍
+OCCURRED IN␍
+renaming module funpatt␍

testsuite/compiler/renamer/varpatt.gf

@@ -0,0 +1,13 @@
+abstract varpatt = {
+
+-- this should raise error
+-- we cannot pattern match on functions
+
+cat D ;
+fun D1 : D ;
+    D2 : D ;
+
+fun d : D -> Int ;
+def d x = 1 ;
+
+}

testsuite/compiler/renamer/varpatt.gfs

@@ -0,0 +1,4 @@
+i -src testsuite/compiler/renamer/varpatt.gf
+
+pt -compute d D1
+pt -compute d D2

testsuite/compiler/renamer/varpatt.gfs.gold

@@ -0,0 +1,4 @@
+1␍
+␍
+1␍
+␍