From 2242cc9c8202132631bd4d845cc3ce17a764363c Mon Sep 17 00:00:00 2001
From: Daniel Chao <dan.chao@apple.com>
Date: Wed, 22 Jul 2026 13:04:36 -0700
Subject: [PATCH] Fix variable resolution of object body params (#1788)

Fixes a regression introduced in Pkl 0.32.
---
 .../main/java/org/pkl/core/ast/builder/SymbolTable.java  | 7 +++++++
 .../input/generators/forGeneratorObjectBodyParam.pkl     | 9 +++++++++
 .../input/generators/whenGeneratorObjectBodyParam.pkl    | 8 ++++++++
 .../output/generators/forGeneratorObjectBodyParam.pcf    | 7 +++++++
 .../output/generators/whenGeneratorObjectBodyParam.pcf   | 5 +++++
 5 files changed, 36 insertions(+)
 create mode 100644 pkl-core/src/test/files/LanguageSnippetTests/input/generators/forGeneratorObjectBodyParam.pkl
 create mode 100644 pkl-core/src/test/files/LanguageSnippetTests/input/generators/whenGeneratorObjectBodyParam.pkl
 create mode 100644 pkl-core/src/test/files/LanguageSnippetTests/output/generators/forGeneratorObjectBodyParam.pcf
 create mode 100644 pkl-core/src/test/files/LanguageSnippetTests/output/generators/whenGeneratorObjectBodyParam.pcf

diff --git a/pkl-core/src/main/java/org/pkl/core/ast/builder/SymbolTable.java b/pkl-core/src/main/java/org/pkl/core/ast/builder/SymbolTable.java
index 6dccb304b..fe39738fe 100644
--- a/pkl-core/src/main/java/org/pkl/core/ast/builder/SymbolTable.java
+++ b/pkl-core/src/main/java/org/pkl/core/ast/builder/SymbolTable.java
@@ -523,6 +523,13 @@ public final class SymbolTable {
         if (scope instanceof LexicalScope lex) {
           if (shouldSkip && !(scope instanceof ForGeneratorScope)) {
             if (scope instanceof ObjectScope objectScope && objectScope.hasParams()) {
+              // skipping the object scope should now see the object body params, because the params
+              // are one level higher than the body itself.
+              var result = fun.apply(objectScope, levelsUp);
+              if (result instanceof Parameter parameter) {
+                //noinspection unchecked
+                return (R) new Parameter(parameter.slot(), parameter.levelsUp() - 1);
+              }
               levelsUp++;
             }
             // An EagerGeneratorScope (for `when` predicates) skipped an ObjectScope.
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/input/generators/forGeneratorObjectBodyParam.pkl b/pkl-core/src/test/files/LanguageSnippetTests/input/generators/forGeneratorObjectBodyParam.pkl
new file mode 100644
index 000000000..bf50f60bd
--- /dev/null
+++ b/pkl-core/src/test/files/LanguageSnippetTests/input/generators/forGeneratorObjectBodyParam.pkl
@@ -0,0 +1,9 @@
+foo = new Mapping {
+  default { key ->
+    for (idx, char in key.split("")) {
+      ["\(char)_\(idx)"] = "hi"
+    }
+  }
+  ["zzz"] {}
+}
+
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/input/generators/whenGeneratorObjectBodyParam.pkl b/pkl-core/src/test/files/LanguageSnippetTests/input/generators/whenGeneratorObjectBodyParam.pkl
new file mode 100644
index 000000000..c015d29c9
--- /dev/null
+++ b/pkl-core/src/test/files/LanguageSnippetTests/input/generators/whenGeneratorObjectBodyParam.pkl
@@ -0,0 +1,8 @@
+foo = new Mapping {
+  default { key ->
+    when (key is String) {
+      bar = key
+    }
+  }
+  ["x"] {}
+}
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/output/generators/forGeneratorObjectBodyParam.pcf b/pkl-core/src/test/files/LanguageSnippetTests/output/generators/forGeneratorObjectBodyParam.pcf
new file mode 100644
index 000000000..d3a6a695d
--- /dev/null
+++ b/pkl-core/src/test/files/LanguageSnippetTests/output/generators/forGeneratorObjectBodyParam.pcf
@@ -0,0 +1,7 @@
+foo {
+  ["zzz"] {
+    ["z_0"] = "hi"
+    ["z_1"] = "hi"
+    ["z_2"] = "hi"
+  }
+}
diff --git a/pkl-core/src/test/files/LanguageSnippetTests/output/generators/whenGeneratorObjectBodyParam.pcf b/pkl-core/src/test/files/LanguageSnippetTests/output/generators/whenGeneratorObjectBodyParam.pcf
new file mode 100644
index 000000000..8e4aa6bfb
--- /dev/null
+++ b/pkl-core/src/test/files/LanguageSnippetTests/output/generators/whenGeneratorObjectBodyParam.pcf
@@ -0,0 +1,5 @@
+foo {
+  ["x"] {
+    bar = "x"
+  }
+}