From 591192c3e582b9a750a30be8b00368c49b7ddbec Mon Sep 17 00:00:00 2001
From: Kampfkarren <boynedmaster@gmail.com>
Date: Tue, 26 Jul 2022 23:06:56 -0700
Subject: [PATCH] Fix location, Transpiler

---
 Analysis/src/Transpiler.cpp | 22 ++++++++++++++++++++++
 Ast/src/Parser.cpp          |  6 ++++--
 tests/JsonEncoder.test.cpp  |  2 +-
 tests/Transpiler.test.cpp   | 10 ++++++++++
 4 files changed, 37 insertions(+), 3 deletions(-)

diff --git a/Analysis/src/Transpiler.cpp b/Analysis/src/Transpiler.cpp
index 9feff1c0..d0bdf4a4 100644
--- a/Analysis/src/Transpiler.cpp
+++ b/Analysis/src/Transpiler.cpp
@@ -511,6 +511,28 @@ struct Printer
             writer.keyword("else");
             visualize(*a->falseExpr);
         }
+        else if (const auto& a = expr.as<AstExprInterpString>())
+        {
+            writer.symbol("`");
+
+            size_t index = 0;
+
+            for (const auto& string : a->strings)
+            {
+                writer.write(escape(std::string_view(string.data, string.size)));
+
+                if (index < a->expressions.size)
+                {
+                    writer.symbol("{");
+                    visualize(*a->expressions.data[index]);
+                    writer.symbol("}");
+                }
+
+                index++;
+            }
+
+            writer.symbol("`");
+        }
         else if (const auto& a = expr.as<AstExprError>())
         {
             writer.symbol("(error-expr");
diff --git a/Ast/src/Parser.cpp b/Ast/src/Parser.cpp
index 440be35b..9a9ac315 100644
--- a/Ast/src/Parser.cpp
+++ b/Ast/src/Parser.cpp
@@ -2638,6 +2638,8 @@ AstExpr* Parser::parseInterpString()
     std::vector<AstArray<char>> strings;
     std::vector<AstExpr*> expressions;
 
+    Location startLocation = lexer.current().location;
+
     do {
         auto currentLexeme = lexer.current();
         LUAU_ASSERT(currentLexeme.type == Lexeme::InterpStringBegin || currentLexeme.type == Lexeme::InterpStringMid || currentLexeme.type == Lexeme::InterpStringEnd);
@@ -2651,7 +2653,7 @@ AstExpr* Parser::parseInterpString()
         if (!Lexer::fixupQuotedString(scratchData))
         {
             nextLexeme();
-            return reportExprError(location, {}, "Interpolated string literal contains malformed escape sequence");
+            return reportExprError(startLocation, {}, "Interpolated string literal contains malformed escape sequence");
         }
 
         AstArray<char> chars = copy(scratchData);
@@ -2670,7 +2672,7 @@ AstExpr* Parser::parseInterpString()
             AstArray<AstArray<char>> stringsArray = copy(strings.data(), strings.size());
             AstArray<AstExpr*> expressionsArray = copy(expressions.data(), expressions.size());
 
-            return allocator.alloc<AstExprInterpString>(location, stringsArray, expressionsArray);
+            return allocator.alloc<AstExprInterpString>(startLocation, stringsArray, expressionsArray);
         }
 
         AstExpr* expression = parseExpr();
diff --git a/tests/JsonEncoder.test.cpp b/tests/JsonEncoder.test.cpp
index 99bb3187..7d7b18d7 100644
--- a/tests/JsonEncoder.test.cpp
+++ b/tests/JsonEncoder.test.cpp
@@ -183,7 +183,7 @@ TEST_CASE_FIXTURE(JsonEncoderFixture, "encode_AstExprInterpString")
     AstStat* statement = expectParseStatement("local a = `var = {x}`");
 
     std::string_view expected =
-        R"({"type":"AstStatLocal","location":"0,0 - 0,21","vars":[{"luauType":null,"name":"a","type":"AstLocal","location":"0,6 - 0,7"}],"values":[{"type":"AstExprInterpString","location":"0,20 - 0,21","strings":["var = ",""],"expressions":[{"type":"AstExprGlobal","location":"0,18 - 0,19","global":"x"}]}]})";
+        R"({"type":"AstStatLocal","location":"0,0 - 0,17","vars":[{"luauType":null,"name":"a","type":"AstLocal","location":"0,6 - 0,7"}],"values":[{"type":"AstExprInterpString","location":"0,10 - 0,17","strings":["var = ",""],"expressions":[{"type":"AstExprGlobal","location":"0,18 - 0,19","global":"x"}]}]})";
 
     CHECK(toJson(statement) == expected);
 }
diff --git a/tests/Transpiler.test.cpp b/tests/Transpiler.test.cpp
index d2ed9aef..d6eac999 100644
--- a/tests/Transpiler.test.cpp
+++ b/tests/Transpiler.test.cpp
@@ -6,6 +6,7 @@
 #include "Luau/Transpiler.h"
 
 #include "Fixture.h"
+#include "ScopedFlags.h"
 
 #include "doctest.h"
 
@@ -678,4 +679,13 @@ TEST_CASE_FIXTURE(Fixture, "transpile_for_in_multiple_types")
     CHECK_EQ(code, transpile(code, {}, true).code);
 }
 
+TEST_CASE_FIXTURE(Fixture, "transpile_string_interp")
+{
+    ScopedFastFlag sff{"LuauInterpolatedStringBaseSupport", true};
+
+    std::string code = R"( local _ = `hello {name}` )";
+
+    CHECK_EQ(code, transpile(code, {}, true).code);
+}
+
 TEST_SUITE_END();