From 3ce7bd194097d7bec980ca8467fb36bf7234b7ff Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Thu, 17 Oct 2019 13:23:06 -0700
Subject: [PATCH 1/4] Fix stack overflow in circular assignment declaration

It also needs to have multiple assignments so that it has a ValueModule
flag.

Fixes #33006
---
 src/compiler/checker.ts                       |  3 ---
 ...cularMultipleAssignmentDeclaration.symbols | 15 +++++++++++
 ...ircularMultipleAssignmentDeclaration.types | 25 +++++++++++++++++++
 .../circularMultipleAssignmentDeclaration.ts  |  6 +++++
 4 files changed, 46 insertions(+), 3 deletions(-)
 create mode 100644 tests/baselines/reference/circularMultipleAssignmentDeclaration.symbols
 create mode 100644 tests/baselines/reference/circularMultipleAssignmentDeclaration.types
 create mode 100644 tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 3228b6bf1dff4..255e07c6654c7 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7270,9 +7270,6 @@ namespace ts {
             // Handle variable, parameter or property
             if (!pushTypeResolution(symbol, TypeSystemPropertyName.Type)) {
                 // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
-                if (symbol.flags & SymbolFlags.ValueModule) {
-                    return getTypeOfFuncClassEnumModule(symbol);
-                }
                 return reportCircularityError(symbol);
             }
             let type: Type | undefined;
diff --git a/tests/baselines/reference/circularMultipleAssignmentDeclaration.symbols b/tests/baselines/reference/circularMultipleAssignmentDeclaration.symbols
new file mode 100644
index 0000000000000..c298d31ee7c0c
--- /dev/null
+++ b/tests/baselines/reference/circularMultipleAssignmentDeclaration.symbols
@@ -0,0 +1,15 @@
+=== tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.js ===
+ns.next = ns.next || { shared: {} };
+>ns.next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+>ns : Symbol(ns, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 0, 36))
+>next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+>ns.next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+>ns : Symbol(ns, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 0, 36))
+>next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+>shared : Symbol(shared, Decl(circularMultipleAssignmentDeclaration.js, 0, 22))
+
+ns.next.shared.mymethod = {};
+>ns.next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+>ns : Symbol(ns, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 0, 36))
+>next : Symbol(ns.next, Decl(circularMultipleAssignmentDeclaration.js, 0, 0), Decl(circularMultipleAssignmentDeclaration.js, 1, 3))
+
diff --git a/tests/baselines/reference/circularMultipleAssignmentDeclaration.types b/tests/baselines/reference/circularMultipleAssignmentDeclaration.types
new file mode 100644
index 0000000000000..6b5239ed4e475
--- /dev/null
+++ b/tests/baselines/reference/circularMultipleAssignmentDeclaration.types
@@ -0,0 +1,25 @@
+=== tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.js ===
+ns.next = ns.next || { shared: {} };
+>ns.next = ns.next || { shared: {} } : any
+>ns.next : any
+>ns : typeof ns
+>next : any
+>ns.next || { shared: {} } : any
+>ns.next : any
+>ns : typeof ns
+>next : any
+>{ shared: {} } : { shared: {}; }
+>shared : {}
+>{} : {}
+
+ns.next.shared.mymethod = {};
+>ns.next.shared.mymethod = {} : {}
+>ns.next.shared.mymethod : any
+>ns.next.shared : any
+>ns.next : any
+>ns : typeof ns
+>next : any
+>shared : any
+>mymethod : any
+>{} : {}
+
diff --git a/tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.ts b/tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.ts
new file mode 100644
index 0000000000000..bc2c992dafcc8
--- /dev/null
+++ b/tests/cases/conformance/salsa/circularMultipleAssignmentDeclaration.ts
@@ -0,0 +1,6 @@
+// @filename:circularMultipleAssignmentDeclaration.js
+// @allowJs: true
+// @checkJs: true
+// @noEmit: true
+ns.next = ns.next || { shared: {} };
+ns.next.shared.mymethod = {};

From e7132e201473b14ea7a72710743de9438e430e25 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Thu, 17 Oct 2019 13:26:02 -0700
Subject: [PATCH 2/4] remove errant comment

---
 src/compiler/checker.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 255e07c6654c7..d20c43088f176 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7269,7 +7269,6 @@ namespace ts {
 
             // Handle variable, parameter or property
             if (!pushTypeResolution(symbol, TypeSystemPropertyName.Type)) {
-                // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
                 return reportCircularityError(symbol);
             }
             let type: Type | undefined;

From 4952683491e2bbc22b3ebcd94250aecf3173a40d Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Thu, 17 Oct 2019 13:35:58 -0700
Subject: [PATCH 3/4] Remove other possible circularity

---
 src/compiler/checker.ts | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index d20c43088f176..b40d523ee0de9 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7335,10 +7335,6 @@ namespace ts {
             }
 
             if (!popTypeResolution()) {
-                // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
-                if (symbol.flags & SymbolFlags.ValueModule) {
-                    return getTypeOfFuncClassEnumModule(symbol);
-                }
                 return reportCircularityError(symbol);
             }
             return type;

From e55b30ad187c7a2fff0e400b5b97bbc913b19ff5 Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <293473+sandersn@users.noreply.github.com>
Date: Fri, 18 Oct 2019 08:37:44 -0700
Subject: [PATCH 4/4] Restore fallback with additional condition

---
 src/compiler/checker.ts | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index b40d523ee0de9..e98d96b6fed34 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -7269,6 +7269,10 @@ namespace ts {
 
             // Handle variable, parameter or property
             if (!pushTypeResolution(symbol, TypeSystemPropertyName.Type)) {
+                // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
+                if (symbol.flags & SymbolFlags.ValueModule && !(symbol.flags & SymbolFlags.Assignment)) {
+                    return getTypeOfFuncClassEnumModule(symbol);
+                }
                 return reportCircularityError(symbol);
             }
             let type: Type | undefined;
@@ -7335,6 +7339,10 @@ namespace ts {
             }
 
             if (!popTypeResolution()) {
+                // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
+                if (symbol.flags & SymbolFlags.ValueModule && !(symbol.flags & SymbolFlags.Assignment)) {
+                    return getTypeOfFuncClassEnumModule(symbol);
+                }
                 return reportCircularityError(symbol);
             }
             return type;