From 2e978d1ac14a9a60ae901ce3403b31ad385a40f9 Mon Sep 17 00:00:00 2001
From: Ivan Timokhin <dev@ivan.timokhin.name>
Date: Wed, 1 Apr 2020 08:45:09 +0300
Subject: [PATCH] Unset TMPDIR before calling tempnam in tempname

tempnam consults the TMPDIR environment variable before its argument,
so if it is set the function will suddenly and quietly ignore the
`parent` argument.
---
 base/file.jl | 4 +++-
 test/file.jl | 9 +++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/base/file.jl b/base/file.jl
index 9e91f433f2942..9ed305d5ff9ea 100644
--- a/base/file.jl
+++ b/base/file.jl
@@ -547,7 +547,9 @@ else # !windows
 # Obtain a temporary filename.
 function tempname(parent::AbstractString=tempdir(); cleanup::Bool=true)
     isdir(parent) || throw(ArgumentError("$(repr(parent)) is not a directory"))
-    p = ccall(:tempnam, Cstring, (Cstring, Cstring), parent, temp_prefix)
+    p = withenv("TMPDIR" => nothing) do
+        ccall(:tempnam, Cstring, (Cstring, Cstring), parent, temp_prefix)
+    end
     systemerror(:tempnam, p == C_NULL)
     s = unsafe_string(p)
     Libc.free(p)
diff --git a/test/file.jl b/test/file.jl
index 74a42cf7275a5..66335fb2f6340 100644
--- a/test/file.jl
+++ b/test/file.jl
@@ -72,6 +72,15 @@ end
     @test_throws ArgumentError tempname(randstring())
 end
 
+@testset "tempname with parent and TMPDIR" begin
+    withenv("TMPDIR" => tempdir()) do
+        mktempdir() do d
+            t = tempname(d)
+            @test dirname(t) == d
+        end
+    end
+end
+
 child_eval(code::String) = eval(Meta.parse(readchomp(`$(Base.julia_cmd()) -E $code`)))
 
 @testset "mktemp/dir basic cleanup" begin