From: NeilBrown <neil@brown.name>
Date: Sat, 18 May 2019 13:51:24 +0000 (+1000)
Subject: oceani: fix merging of conditionally-scoped variables.
X-Git-Tag: JamisonCreek-3~4
X-Git-Url: https://ocean-lang.org/code/?p=ocean;a=commitdiff_plain;h=1ca9cccf579ea6d70d09c837e317aaed64a9f988

oceani: fix merging of conditionally-scoped variables.

The problem here was that the list seen in ->in_scope
includes more than just what is currently in-scope.
It also contains things that have been replaced by new instances
of the name.
These can be detected a they aren't the first variable listed
under their name any more.

Signed-off-by: NeilBrown <neil@brown.name>
---

diff --git a/csrc/oceani-tests.mdc b/csrc/oceani-tests.mdc
index 42505ce..102c957 100644
--- a/csrc/oceani-tests.mdc
+++ b/csrc/oceani-tests.mdc
@@ -163,6 +163,27 @@ Now some contants
 	are there 5 ?
 	3.14159 I like Pie but The cake is a lie
 
+Test merging of variables from multiple cases
+
+###### test list
+	oceani_tests += varmerge
+
+###### test: varmerge
+
+	program:
+		for i:=0; then i=i+1; while i < 5:
+			switch i
+				case 0: num:="zero"
+				case 1: num:="one"
+				case 2: num:="two"
+				case 3: num:="three"
+				else:   num:="many"
+			print num,", ",
+		print
+
+###### output: varmerge
+	zero , one , two , three , many , 
+
 ## Conditions and Loops
 
 Now we need to test if/else and some different loops
diff --git a/csrc/oceani.mdc b/csrc/oceani.mdc
index 1cf84ed..6b43096 100644
--- a/csrc/oceani.mdc
+++ b/csrc/oceani.mdc
@@ -1172,7 +1172,7 @@ all pending-scope variables become conditionally scoped.
 		switch (v ? v->scope : OutScope) {
 		case OutScope:
 		case PendingScope:
-			/* Signal an error - once that is possible */
+			/* Caller will report the error */
 			return NULL;
 		case CondScope:
 			/* All CondScope variables of this name need to be merged
@@ -1193,14 +1193,14 @@ all pending-scope variables become conditionally scoped.
 
 	static void var_block_close(struct parse_context *c, enum closetype ct)
 	{
-		/* close of all variables that are in_scope */
+		/* Close off all variables that are in_scope */
 		struct variable *v, **vp, *v2;
 
 		scope_pop(c);
 		for (vp = &c->in_scope;
 		     v = *vp, v && v->depth > c->scope_depth && v->min_depth > c->scope_depth;
 		     ) {
-			switch (ct) {
+			if (v->name->var == v) switch (ct) {
 			case CloseElse:
 			case CloseParallel: /* handle PendingScope */
 				switch(v->scope) {
@@ -1261,7 +1261,7 @@ all pending-scope variables become conditionally scoped.
 				}
 				break;
 			}
-			if (v->scope == OutScope)
+			if (v->scope == OutScope || v->name->var != v)
 				*vp = v->in_scope;
 			else
 				vp = &v->in_scope;