Merge pull request #5014 from mestorlx/develop

Improve error message for lookup in function types

7 files changed, 105 insertions, 2 deletions

diff --git a/Changelog.md b/Changelog.md
index 2d6f518c..465a9daa 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -99,6 +99,7 @@ Compiler Features:
  * Tests: Determine transaction status during IPC calls.
  * Code Generator: Allocate and free local variables according to their scope.
  * Removed ``pragma experimental "v0.5.0";``.
+ * Syntax Checker: Improved error message for lookup in function types.
 
 Bugfixes:
  * Build System: Support versions of CVC4 linked against CLN instead of GMP. In case of compilation issues due to the experimental SMT solver support, the solvers can be disabled when configuring the project with CMake using ``-DUSE_CVC4=OFF`` or ``-DUSE_Z3=OFF``.
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 39ea494d..5ffdda57 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -2141,8 +2141,25 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 				);
 		}
 		string errorMsg = "Member \"" + memberName + "\" not found or not visible "
-				"after argument-dependent lookup in " + exprType->toString() +
-				(memberName == "value" ? " - did you forget the \"payable\" modifier?" : ".");
+				"after argument-dependent lookup in " + exprType->toString() + ".";
+		if (memberName == "value")
+		{
+			errorMsg.pop_back();
+			errorMsg +=	" - did you forget the \"payable\" modifier?";
+		}
+		else if (exprType->category() == Type::Category::Function)
+		{
+			if (auto const& funType = dynamic_pointer_cast<FunctionType const>(exprType))
+			{
+				auto const& t = funType->returnParameterTypes();
+				if (t.size() == 1)
+					if (
+						t.front()->category() == Type::Category::Contract ||
+						t.front()->category() == Type::Category::Struct
+					)
+						errorMsg += " Did you intend to call the function?";
+			}
+		}
 		if (exprType->category() == Type::Category::Contract)
 			for (auto const& addressMember: AddressType::addressPayable().nativeMembers(nullptr))
 				if (addressMember.name == memberName)
diff --git a/test/libsolidity/syntaxTests/nameAndTypeResolution/575_member_member_getter_call_without_parentheses.sol b/test/libsolidity/syntaxTests/nameAndTypeResolution/575_member_member_getter_call_without_parentheses.sol
new file mode 100644
index 00000000..61f43103
--- /dev/null
+++ b/test/libsolidity/syntaxTests/nameAndTypeResolution/575_member_member_getter_call_without_parentheses.sol
@@ -0,0 +1,19 @@
+contract A{
+    function f() public pure{
+
+    }
+}
+contract B{
+    A public a;
+}
+contract C{
+    B public b;
+}
+contract D{
+    C c;
+    function f() public view{
+        c.b.a.f();
+    }
+}
+// ----
+// TypeError: (170-175): Member "a" not found or not visible after argument-dependent lookup in function () view external returns (contract B). Did you intend to call the function?
diff --git a/test/libsolidity/syntaxTests/nameAndTypeResolution/576_member_getter_call_without_parentheses.sol b/test/libsolidity/syntaxTests/nameAndTypeResolution/576_member_getter_call_without_parentheses.sol
new file mode 100644
index 00000000..bdc5fdc7
--- /dev/null
+++ b/test/libsolidity/syntaxTests/nameAndTypeResolution/576_member_getter_call_without_parentheses.sol
@@ -0,0 +1,17 @@
+contract A{
+    function f() public pure{
+
+    }
+}
+contract B{
+    A public a;
+}
+contract C{
+    B b;
+    function f() public view{
+        b.a.f();
+    }
+}
+
+// ----
+// TypeError: (140-145): Member "f" not found or not visible after argument-dependent lookup in function () view external returns (contract A). Did you intend to call the function?
diff --git a/test/libsolidity/syntaxTests/nameAndTypeResolution/577_member_getter_call_without_parentheses_missing_function.sol b/test/libsolidity/syntaxTests/nameAndTypeResolution/577_member_getter_call_without_parentheses_missing_function.sol
new file mode 100644
index 00000000..d204d926
--- /dev/null
+++ b/test/libsolidity/syntaxTests/nameAndTypeResolution/577_member_getter_call_without_parentheses_missing_function.sol
@@ -0,0 +1,15 @@
+contract A{
+
+}
+contract B{
+    A public a;
+}
+contract C{
+    B b;
+    function f() public view{
+        b.a.f();
+    }
+}
+
+// ----
+// TypeError: (104-109): Member "f" not found or not visible after argument-dependent lookup in function () view external returns (contract A). Did you intend to call the function?
diff --git a/test/libsolidity/syntaxTests/nameAndTypeResolution/578_private_member_getter_call_without_parentheses.sol b/test/libsolidity/syntaxTests/nameAndTypeResolution/578_private_member_getter_call_without_parentheses.sol
new file mode 100644
index 00000000..e71da372
--- /dev/null
+++ b/test/libsolidity/syntaxTests/nameAndTypeResolution/578_private_member_getter_call_without_parentheses.sol
@@ -0,0 +1,17 @@
+contract A{
+    function f() public pure{
+
+    }
+}
+contract B{
+    A private a;
+}
+contract C{
+    B b;
+    function f() public view{
+        b.a.f();
+    }
+}
+
+// ----
+// TypeError: (141-144): Member "a" not found or not visible after argument-dependent lookup in contract B.
diff --git a/test/libsolidity/syntaxTests/nameAndTypeResolution/579_member_getter_call_without_parentheses_private_function.sol b/test/libsolidity/syntaxTests/nameAndTypeResolution/579_member_getter_call_without_parentheses_private_function.sol
new file mode 100644
index 00000000..18932238
--- /dev/null
+++ b/test/libsolidity/syntaxTests/nameAndTypeResolution/579_member_getter_call_without_parentheses_private_function.sol
@@ -0,0 +1,17 @@
+contract A{
+    function f() private pure{
+
+    }
+}
+contract B{
+    A public a;
+}
+contract C{
+    B b;
+    function f() public view{
+        b.a.f();
+    }
+}
+
+// ----
+// TypeError: (141-146): Member "f" not found or not visible after argument-dependent lookup in function () view external returns (contract A). Did you intend to call the function?