refactor(semantic): eliminate manual current_node_ix manipulation in try statements (#14858)

fixes the `TODO`​ comments left in the code

Author: camc314

crates/oxc_semantic/src/builder.rs

@@ -1573,12 +1573,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
             self.visit_catch_clause(handler);
 
             /* cfg */
-            control_flow!(self, |cfg| {
-                let catch_block_end_ix = cfg.current_node_ix;
-                // TODO: we shouldn't directly change the current node index.
-                cfg.current_node_ix = after_try_block_graph_ix;
-                Some(catch_block_end_ix)
-            })
+            control_flow!(self, |cfg| Some(cfg.current_node_ix))
             /* cfg */
         } else {
             None
@@ -1605,12 +1600,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
             self.visit_block_statement(finalizer);
 
             /* cfg */
-            control_flow!(self, |cfg| {
-                let finally_block_end_ix = cfg.current_node_ix;
-                // TODO: we shouldn't directly change the current node index.
-                cfg.current_node_ix = after_try_block_graph_ix;
-                Some(finally_block_end_ix)
-            })
+            control_flow!(self, |cfg| Some(cfg.current_node_ix))
             /* cfg */
         } else {
             None
@@ -1623,7 +1613,6 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
 
         /* cfg */
         control_flow!(self, |cfg| {
-            let after_try_statement_block_ix = cfg.new_basic_block_normal();
             cfg.add_edge(
                 before_try_statement_graph_ix,
                 before_try_block_graph_ix,
@@ -1632,6 +1621,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
             if let Some(catch_block_end_ix) = catch_block_end_ix
                 && finally_block_end_ix.is_none()
             {
+                let after_try_statement_block_ix = cfg.new_basic_block_normal();
                 cfg.add_edge(
                     after_try_block_graph_ix,
                     after_try_statement_block_ix,
@@ -1641,6 +1631,7 @@ impl<'a> Visit<'a> for SemanticBuilder<'a> {
                 cfg.add_edge(catch_block_end_ix, after_try_statement_block_ix, EdgeType::Normal);
             }
             if let Some(finally_block_end_ix) = finally_block_end_ix {
+                let after_try_statement_block_ix = cfg.new_basic_block_normal();
                 if catch_block_end_ix.is_some() {
                     cfg.add_edge(
                         finally_block_end_ix,

crates/oxc_semantic/tests/integration/snapshots/do_while_break.snap

@@ -98,8 +98,8 @@ return" shape = box]
     9 -> 10 [ label="Normal", style="dotted"]
     9 -> 7 [ label="Backedge", style="dotted", color=grey]
     7 -> 10 [ label="Jump", color=green]
-    11 -> 2 [ label="Error(Implicit)", color=red, style=dashed]
     3 -> 5 [ label="Normal"]
+    11 -> 2 [ label="Error(Implicit)", color=red, style=dashed]
     10 -> 11 [ label="Join"]
     12 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     1 -> 12 [ label="Normal"]

crates/oxc_semantic/tests/integration/snapshots/function_in_finally.snap

@@ -65,7 +65,7 @@ ExpressionStatement" shape = box]
     4 -> 6 [ label="NewFunction"]
     7 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     4 -> 7 [ label="Normal"]
-    8 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     1 -> 3 [ label="Normal"]
+    8 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     7 -> 8 [ label="Join"]
 }

crates/oxc_semantic/tests/integration/snapshots/labeled_block_break.snap

@@ -89,8 +89,8 @@ unreachable" shape = box]
     9 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     8 -> 9 [ label="Normal"]
     6 -> 9 [ label="Jump", color=green]
-    10 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     1 -> 3 [ label="Normal"]
+    10 -> 0 [ label="Error(Implicit)", color=red, style=dashed]
     3 -> 10 [ label="Normal"]
     9 -> 10 [ label="Normal"]
 }

crates/oxc_semantic/tests/integration/snapshots/labelled_try_break.snap

@@ -95,8 +95,8 @@ unreachable" shape = box]
     4 -> 7 [ label="Normal"]
     8 -> 2 [ label="Error(Implicit)", style=dashed, color=red]
     7 -> 8 [ label="Unreachable", style="dotted"]
-    9 -> 2 [ label="Error(Implicit)", style=dashed, color=red]
     3 -> 5 [ label="Normal"]
+    9 -> 2 [ label="Error(Implicit)", style=dashed, color=red]
     8 -> 9 [ label="Unreachable", style="dotted"]
     10 -> 2 [ label="Error(Implicit)", color=red, style=dashed]
     9 -> 10 [ label="Normal", style="dotted"]