fix(tvix/glue): do not panic if PathInfoService returns Err r/7128

Nixpkgs tries to `import` the value returned by
`builtins.unsafeGetAttrPos`, which in our case is the file
`/deep/thought`.  Since that doesn't exist, tvix-glue panics, but
there's no interpreter backtrace to follow.

Let's return an Err instead of panicking.

------------------------------------------------------------------------------
Before:

thread 'tokio-runtime-worker' panicked at /source/src/import.rs:164:27:
called `Result::unwrap()` on an `Err` value: Error { depth: 0, inner: Io { path: Some("/deep/thought:42"), err: Os { code: 2, kind: NotFound, message: "No such file or directory" } } }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
thread 'main' panicked at src/tvix_store_io.rs:276:58:
called `Result::unwrap()` on an `Err` value: JoinError::Panic(Id(41580), ...)
Command exited with non-zero status 101

------------------------------------------------------------------------------
After:

thread 'tokio-runtime-worker' panicked at /source/src/import.rs:164:27:
called `Result::unwrap()` on an `Err` value: Error { depth: 0, inner: Io { path: Some("/deep/thought:42"), err: Os { code: 2, kind: NotFound, message: "No such file or directory" } } }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
note: while evaluating this Nix code
   --> [code]:1:1
    |
1   | (import /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src {}).pkgsCross.aarch64-multiplatform.rocmPackages_5.hipblas.outPath
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this Nix code
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/development/rocm-modules/5/llvm/stage-2/bintools-unwrapped.nix:6:78
    |
6   |   runCommand "rocm-llvm-binutils-${llvm.version}" { preferLocalBuild = true; } ''
    |  ______________________________________________________________________________^
7   | |   mkdir -p $out/bin
8   | |
9   | |   for prog in ${lld}/bin/*; do
...   |
27  | |   ln -s ${lld}/bin/lld $out/bin/ld
28  | | ''
    | |__^
note: while evaluating this as native code (coerce_to_string)
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/development/rocm-modules/5/llvm/stage-2/bintools-unwrapped.nix:27:9
    |
27  |   ln -s ${lld}/bin/lld $out/bin/ld
    |         ^^^^^^
note: while evaluating this as native code (getAttr)
   --> <src-builtins/derivation.nix>:26:19
    |
26  |         outPath = builtins.getAttr outputName strict;
    |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (derivationStrict)
   --> <src-builtins/derivation.nix>:14:12
    |
14  |   strict = derivationStrict drvAttrs;
    |            ^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this Nix code
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/lib/customisation.nix:249:23
    |
249 |             outPath = assert condition; drv.${outputName}.outPath;
    |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: while evaluating this as native code (force)
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/lib/customisation.nix:249:30
    |
249 |             outPath = assert condition; drv.${outputName}.outPath;
    |                              ^^^^^^^^^
note: while evaluating this as native code (throw)
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/stdenv/generic/check-meta.nix:262:8
    |
262 |     in handler msg;
    |        ^^^^^^^^^^^
note: while evaluating this Nix code
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/stdenv/generic/check-meta.nix:254:14
    |
254 |           else ''
    |  ______________^
255 | |           Package ‘${getName attrs}’ in ${pos_str meta} ${errormsg}, refusing to evaluate.
256 | |
257 | |         '' + (builtins.getAttr reason remediation) attrs;
    | |________________________________________________________^
note: while evaluating this as native code (force)
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/stdenv/generic/check-meta.nix:254:14
    |
254 |           else ''
    |  ______________^
255 | |           Package ‘${getName attrs}’ in ${pos_str meta} ${errormsg}, refusing to evaluate.
256 | |
257 | |         '' + (builtins.getAttr reason remediation) attrs;
    | |__________^
error[E029]: I/O error: /deep/thought:42: task panicked
   --> /nix/store/7xii7xcl0iliqxfq8hp577wdq5j0mikr-kp8vf3gzk1pff9r40j5p0y8kiwhkkqw1-nixpkgs-src/pkgs/stdenv/generic/check-meta.nix:255:41
    |
255 |           Package ‘${getName attrs}’ in ${pos_str meta} ${errormsg}, refusing to evaluate.
    |                                         ^^^^^^^^^^^^^^^

Command exited with non-zero status 1
Benchmark: {"pkgsCross.aarch64-multiplatform.rocmPackages_5.hipblas.outPath":{"kbytes":"26613180","system":"22.35","user":"140.62"}}

Change-Id: I587b57e9e49d1f3ecdc0fc9cf996d179a3548f34
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10223
Autosubmit: Adam Joseph <adam@westernsemico.com>
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

1 files changed, 1 insertions, 1 deletions

diff --git a/tvix/glue/src/tvix_store_io.rs b/tvix/glue/src/tvix_store_io.rs
index 3f462df3dc..3cd59d559a 100644
--- a/tvix/glue/src/tvix_store_io.rs
+++ b/tvix/glue/src/tvix_store_io.rs
@@ -273,7 +273,7 @@ impl EvalIO for TvixStoreIO {
             import_path_with_pathinfo(blob_service, directory_service, path_info_service, &p).await
         });
 
-        let path_info = self.tokio_handle.block_on(task).unwrap()?;
+        let path_info = self.tokio_handle.block_on(task)??;
 
         // from the [PathInfo], extract the store path (as string).
         Ok({