From 8d9a26fec09d94b5474f7e0c3fd91123a17e9b55 Mon Sep 17 00:00:00 2001
From: Hisham Muhammad <hisham@gobolinux.org>
Date: Fri, 3 Jan 2025 12:05:35 -0300
Subject: [PATCH] fix: do not get file names and locations out of sync in error
 messages

---
 .../error_reporting/typecheck_error_spec.lua  | 29 +++++++++++++++++++
 tl.lua                                        | 18 +++++-------
 tl.tl                                         | 17 +++++------
 3 files changed, 44 insertions(+), 20 deletions(-)

diff --git a/spec/lang/error_reporting/typecheck_error_spec.lua b/spec/lang/error_reporting/typecheck_error_spec.lua
index 5afa15723..73928f93e 100644
--- a/spec/lang/error_reporting/typecheck_error_spec.lua
+++ b/spec/lang/error_reporting/typecheck_error_spec.lua
@@ -153,4 +153,33 @@ describe("typecheck errors", function()
       })
    end)
 
+   it("do not confuse filenames", function ()
+      util.mock_io(finally, {
+         ["ordering.tl"] = [[
+            local record ordering
+               type SortBy<K> = table.SortFunction<K>
+            end
+
+            return ordering
+         ]],
+         ["util.tl"] = [[
+            local type SortBy = require("ordering").SortBy
+
+            local record util
+               func: function(sort_by?: SortBy)
+            end
+
+            return util
+         ]]
+      })
+      util.run_check_type_error([[
+         local util = require("util")
+
+         util.func(function() end)
+         print("this is where the error should not be")
+      ]], {
+         { y = 4, x = 41, filename = "./util.tl", msg = "missing type argument" }
+      })
+   end)
+
 end)
diff --git a/tl.lua b/tl.lua
index 4f9861d81..26216861a 100644
--- a/tl.lua
+++ b/tl.lua
@@ -1680,9 +1680,6 @@ local table_types = {
 
 
 
-
-
-
 
 local function is_numeric_type(t)
    return t.typename == "number" or t.typename == "integer"
@@ -6250,10 +6247,10 @@ local function Err_at(w, msg)
    }
 end
 
-local function insert_error(self, y, x, err)
+local function insert_error(self, y, x, f, err)
    err.y = assert(y)
    err.x = assert(x)
-   err.filename = self.filename
+   err.filename = assert(f)
 
    if TL_DEBUG then
       io.stderr:write("ERROR:" .. err.y .. ":" .. err.x .. ": " .. err.msg .. "\n")
@@ -6265,7 +6262,7 @@ end
 function Errors:add(w, msg, ...)
    local e = Err(msg, ...)
    if e then
-      insert_error(self, w.y, w.x, e)
+      insert_error(self, w.y, w.x, w.f, e)
    end
 end
 
@@ -6292,14 +6289,14 @@ function Errors:add_in_context(w, ctx, msg, ...)
 
    local e = Err(msg, ...)
    if e then
-      insert_error(self, w.y, w.x, e)
+      insert_error(self, w.y, w.x, w.f, e)
    end
 end
 
 
 function Errors:collect(errs)
    for _, e in ipairs(errs) do
-      insert_error(self, e.y, e.x, e)
+      insert_error(self, e.y, e.x, e.filename, e)
    end
 end
 
@@ -6309,7 +6306,7 @@ function Errors:add_warning(tag, w, fmt, ...)
       y = w.y,
       x = w.x,
       msg = fmt:format(...),
-      filename = self.filename,
+      filename = assert(w.f),
       tag = tag,
    })
 end
@@ -6384,7 +6381,7 @@ function Errors:add_prefixing(w, src, prefix, dst)
       if dst then
          table.insert(dst, err)
       else
-         insert_error(self, err.y, err.x, err)
+         insert_error(self, err.y, err.x, err.filename, err)
       end
    end
 end
@@ -7482,6 +7479,7 @@ do
          typ = fields[names[i]]
       end
 
+
       if typ and typ.typename == "nominal" then
          typ = typ.found
       end
diff --git a/tl.tl b/tl.tl
index f04b2395f..f4d8d47b3 100644
--- a/tl.tl
+++ b/tl.tl
@@ -1668,9 +1668,6 @@ local interface Type
    is Where
    where self.typename
 
-   y: integer
-   x: integer
-
    typename: TypeName    -- discriminator
    typeid: integer       -- unique identifier
    inferred_at: Where    -- for error messages
@@ -6250,10 +6247,10 @@ local function Err_at(w: Where, msg: string): Error
    }
 end
 
-local function insert_error(self: Errors, y: integer, x: integer, err: Error)
+local function insert_error(self: Errors, y: integer, x: integer, f: string, err: Error)
    err.y = assert(y)
    err.x = assert(x)
-   err.filename = self.filename
+   err.filename = assert(f)
 
    if TL_DEBUG then
       io.stderr:write("ERROR:" .. err.y .. ":" .. err.x .. ": " .. err.msg .. "\n")
@@ -6265,7 +6262,7 @@ end
 function Errors:add(w: Where, msg: string, ...:Type)
    local e = Err(msg, ...)
    if e then
-      insert_error(self, w.y, w.x, e)
+      insert_error(self, w.y, w.x, w.f, e)
    end
 end
 
@@ -6292,14 +6289,14 @@ function Errors:add_in_context(w: Where, ctx: Node, msg: string, ...:Type)
 
    local e = Err(msg, ...)
    if e then
-      insert_error(self, w.y, w.x, e)
+      insert_error(self, w.y, w.x, w.f, e)
    end
 end
 
 
 function Errors:collect(errs: {Error})
    for _, e in ipairs(errs) do
-      insert_error(self, e.y, e.x, e)
+      insert_error(self, e.y, e.x, e.filename, e)
    end
 end
 
@@ -6309,7 +6306,7 @@ function Errors:add_warning(tag: WarningKind, w: Where, fmt: string, ...: any)
       y = w.y,
       x = w.x,
       msg = fmt:format(...),
-      filename = self.filename,
+      filename = assert(w.f),
       tag = tag,
    })
 end
@@ -6384,7 +6381,7 @@ function Errors:add_prefixing(w: Where, src: {Error}, prefix: string, dst?: {Err
       if dst then
          table.insert(dst, err)
       else
-         insert_error(self, err.y, err.x, err)
+         insert_error(self, err.y, err.x, err.filename, err)
       end
    end
 end