From 91a4e55c066b32249b4e1ed5949aeb06b0dff6ef Mon Sep 17 00:00:00 2001
From: Philipp Mildenberger <philipp@mildenberger.me>
Date: Fri, 12 May 2023 00:00:21 +0200
Subject: [PATCH 1/7] Symlink cargo build artifacts instead of copying them

---
 lib/cargoTarpaulin.nix                      |  2 +-
 lib/setupHooks/inheritCargoArtifacts.nix    |  2 +
 lib/setupHooks/inheritCargoArtifactsHook.sh | 42 +++++++++++++++------
 3 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/lib/cargoTarpaulin.nix b/lib/cargoTarpaulin.nix
index 5ac007d9..1b094f82 100644
--- a/lib/cargoTarpaulin.nix
+++ b/lib/cargoTarpaulin.nix
@@ -3,7 +3,7 @@
 }:
 
 { cargoExtraArgs ? ""
-, cargoTarpaulinExtraArgs ? "--skip-clean --out Xml --output-dir $out"
+, cargoTarpaulinExtraArgs ? "--out Xml --output-dir $out"
 , ...
 }@origArgs:
 let
diff --git a/lib/setupHooks/inheritCargoArtifacts.nix b/lib/setupHooks/inheritCargoArtifacts.nix
index afb3d67e..aebdfa86 100644
--- a/lib/setupHooks/inheritCargoArtifacts.nix
+++ b/lib/setupHooks/inheritCargoArtifacts.nix
@@ -1,8 +1,10 @@
 { makeSetupHook
+, rsync
 }:
 
 makeSetupHook
 {
   name = "inheritCargoArtifactsHook";
+  propagatedBuildInputs = [ rsync ];
 } ./inheritCargoArtifactsHook.sh
 
diff --git a/lib/setupHooks/inheritCargoArtifactsHook.sh b/lib/setupHooks/inheritCargoArtifactsHook.sh
index 2456ef1c..fce3e3ea 100644
--- a/lib/setupHooks/inheritCargoArtifactsHook.sh
+++ b/lib/setupHooks/inheritCargoArtifactsHook.sh
@@ -24,18 +24,36 @@ inheritCargoArtifacts() {
   elif [ -d "${preparedArtifacts}" ]; then
     echo "copying cargo artifacts from ${preparedArtifacts} to ${cargoTargetDir}"
 
-    # NB: rustc doesn't like it when artifacts are either symlinks or hardlinks to the store
-    # (it tries to truncate files instead of unlinking and recreating them)
-    # so we're forced to do a full copy here :(
-    #
-    # Notes:
-    # - --no-target-directory to avoid nesting (i.e. `./target/target`)
-    # - preserve timestamps to avoid rebuilding
-    # - no-preserve ownership (root) so we can make the files writable
-    cp -r "${preparedArtifacts}" \
-      --no-target-directory "${cargoTargetDir}" \
-      --preserve=timestamps \
-      --no-preserve=ownership
+    # copy target dir but ignore crate build artifacts
+    rsync -r --chmod=Du=rwx,Dg=rx,Do=rx --exclude "release/build" --exclude "release/deps" --exclude "*/release/build" --exclude "*/release/deps" "${preparedArtifacts}/" "${cargoTargetDir}/"
+
+    link_build_artifacts() {
+      local artifacts="$1"
+      local target="$2"
+
+      if [ -d "${artifacts}/release/deps" ]; then
+        mkdir -p "${target}/release/deps"
+        for dep in $(ls "${artifacts}/release/deps"); do
+          ln -fs "${artifacts}/release/deps/$dep" "${target}/release/deps/$dep"
+        done
+      fi
+
+      if [ -d "${artifacts}/release/build" ]; then
+        mkdir -p "${target}/release/build"
+        for build in $(ls "${artifacts}/release/build"); do
+          ln -fs "${artifacts}/release/build/$build" "${target}/release/build/$build"
+        done
+      fi
+    }
+
+    # symlink crate build artifacts
+    link_build_artifacts "${preparedArtifacts}" "${cargoTargetDir}"
+
+    # for each build target as well
+    # all other directories are ignored in `link_build_artifacts`
+    for target in $(ls "${preparedArtifacts}"); do
+      link_build_artifacts "${preparedArtifacts}/$target" "${cargoTargetDir}/$target"
+    done
 
     # Keep existing permissions (e.g. exectuable), but also make things writable
     # since the store is read-only and cargo would otherwise choke

From c41599656db25662504c561f5c2b381e29621095 Mon Sep 17 00:00:00 2001
From: Philipp Mildenberger <philipp.mildenberger@artfabrik.at>
Date: Thu, 18 May 2023 23:41:37 +0200
Subject: [PATCH 2/7] Simplify build-artifacts symlinking and support all build
 profiles instead of just 'release'

---
 lib/setupHooks/inheritCargoArtifactsHook.sh | 39 +++++----------------
 1 file changed, 9 insertions(+), 30 deletions(-)

diff --git a/lib/setupHooks/inheritCargoArtifactsHook.sh b/lib/setupHooks/inheritCargoArtifactsHook.sh
index fce3e3ea..a55a3109 100644
--- a/lib/setupHooks/inheritCargoArtifactsHook.sh
+++ b/lib/setupHooks/inheritCargoArtifactsHook.sh
@@ -24,36 +24,15 @@ inheritCargoArtifacts() {
   elif [ -d "${preparedArtifacts}" ]; then
     echo "copying cargo artifacts from ${preparedArtifacts} to ${cargoTargetDir}"
 
-    # copy target dir but ignore crate build artifacts
-    rsync -r --chmod=Du=rwx,Dg=rx,Do=rx --exclude "release/build" --exclude "release/deps" --exclude "*/release/build" --exclude "*/release/deps" "${preparedArtifacts}/" "${cargoTargetDir}/"
-
-    link_build_artifacts() {
-      local artifacts="$1"
-      local target="$2"
-
-      if [ -d "${artifacts}/release/deps" ]; then
-        mkdir -p "${target}/release/deps"
-        for dep in $(ls "${artifacts}/release/deps"); do
-          ln -fs "${artifacts}/release/deps/$dep" "${target}/release/deps/$dep"
-        done
-      fi
-
-      if [ -d "${artifacts}/release/build" ]; then
-        mkdir -p "${target}/release/build"
-        for build in $(ls "${artifacts}/release/build"); do
-          ln -fs "${artifacts}/release/build/$build" "${target}/release/build/$build"
-        done
-      fi
-    }
-
-    # symlink crate build artifacts
-    link_build_artifacts "${preparedArtifacts}" "${cargoTargetDir}"
-
-    # for each build target as well
-    # all other directories are ignored in `link_build_artifacts`
-    for target in $(ls "${preparedArtifacts}"); do
-      link_build_artifacts "${preparedArtifacts}/$target" "${cargoTargetDir}/$target"
-    done
+    # copy target dir but ignore content-addressed build artifacts
+    rsync -r --chmod=Du=rwx --exclude "*/build/*" --exclude "*/deps/*" --exclude "*/*/build/*" --exclude "*/*/deps/*" "${preparedArtifacts}/" "${cargoTargetDir}/"
+
+    # symlink all remaining content-addressed artifacts
+    pushd "${cargoTargetDir}"
+      for d in $(ls -d */{deps,build} */*/{deps,build}); do
+          ls "${preparedArtifacts}/${d}" | xargs -P 100 -I '##{}##' ln -fs "${preparedArtifacts}/${d}/##{}##" "${d}/##{}##"
+      done
+    popd
 
     # Keep existing permissions (e.g. exectuable), but also make things writable
     # since the store is read-only and cargo would otherwise choke

From 638ab25a5247dfe1f25b87b6a9ef87b62344a019 Mon Sep 17 00:00:00 2001
From: Ivan Petkov <ivanppetkov@gmail.com>
Date: Tue, 6 Jun 2023 20:45:01 -0700
Subject: [PATCH 3/7] Fix build

---
 lib/mkCargoDerivation.nix                | 2 ++
 lib/setupHooks/inheritCargoArtifacts.nix | 1 -
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/mkCargoDerivation.nix b/lib/mkCargoDerivation.nix
index 76e35cb6..929acb45 100644
--- a/lib/mkCargoDerivation.nix
+++ b/lib/mkCargoDerivation.nix
@@ -5,6 +5,7 @@
 , crateNameFromCargoToml
 , inheritCargoArtifactsHook
 , installCargoArtifactsHook
+, rsync
 , stdenv
 , vendorCargoDeps
 , zstd
@@ -59,6 +60,7 @@ chosenStdenv.mkDerivation (cleanedArgs // {
     configureCargoVendoredDepsHook
     inheritCargoArtifactsHook
     installCargoArtifactsHook
+    rsync
     zstd
   ];
 
diff --git a/lib/setupHooks/inheritCargoArtifacts.nix b/lib/setupHooks/inheritCargoArtifacts.nix
index aebdfa86..d4a8a8fe 100644
--- a/lib/setupHooks/inheritCargoArtifacts.nix
+++ b/lib/setupHooks/inheritCargoArtifacts.nix
@@ -5,6 +5,5 @@
 makeSetupHook
 {
   name = "inheritCargoArtifactsHook";
-  propagatedBuildInputs = [ rsync ];
 } ./inheritCargoArtifactsHook.sh
 

From 799d60f4bffdb2747ae12848abd20985c73ff8c4 Mon Sep 17 00:00:00 2001
From: Ivan Petkov <ivanppetkov@gmail.com>
Date: Mon, 19 Jun 2023 13:06:18 -0700
Subject: [PATCH 4/7] inheritCargoArtifactsHook: symlink dependency rlib and
 rmeta files

---
 lib/setupHooks/inheritCargoArtifactsHook.sh | 52 +++++++++++++++------
 1 file changed, 38 insertions(+), 14 deletions(-)

diff --git a/lib/setupHooks/inheritCargoArtifactsHook.sh b/lib/setupHooks/inheritCargoArtifactsHook.sh
index a55a3109..bc9e57a8 100644
--- a/lib/setupHooks/inheritCargoArtifactsHook.sh
+++ b/lib/setupHooks/inheritCargoArtifactsHook.sh
@@ -24,23 +24,47 @@ inheritCargoArtifacts() {
   elif [ -d "${preparedArtifacts}" ]; then
     echo "copying cargo artifacts from ${preparedArtifacts} to ${cargoTargetDir}"
 
-    # copy target dir but ignore content-addressed build artifacts
-    rsync -r --chmod=Du=rwx --exclude "*/build/*" --exclude "*/deps/*" --exclude "*/*/build/*" --exclude "*/*/deps/*" "${preparedArtifacts}/" "${cargoTargetDir}/"
+    # Dependency .rlib and .rmeta files are content addressed and thus are not written to after
+    # being built (since changing `Cargo.lock` would rebuild everything anyway), which makes them
+    # good candidates for symlinking (esp. since they can make up 60-70% of the artifact directory
+    # on most projects). Thus we ignore them when copying all other artifacts below as we will
+    # symlink them afterwards. Note that we scope these checks to the `/deps` subdirectory; the
+    # workspace's own .rlib and .rmeta files appear one directory up (and these may require being
+    # writable depending on how the actual workspace build is being invoked, so we'll leave them
+    # alone).
+    #
+    # NB: keep the executable bit only if set on the original file
+    # but make all files writable as sometimes read-only files will make the build choke
+    #
+    # NB: cargo also doesn't like it if `.cargo-lock` files remain with a
+    # timestamp in the distant past so we avoid copying them here
+    rsync \
+      --recursive \
+      --links \
+      --times \
+      --chmod=u+w \
+      --executability \
+      --exclude 'deps/*.rlib' \
+      --exclude 'deps/*.rmeta' \
+      --exclude '.cargo-lock' \
+      "${preparedArtifacts}/" \
+      "${cargoTargetDir}/"
 
-    # symlink all remaining content-addressed artifacts
-    pushd "${cargoTargetDir}"
-      for d in $(ls -d */{deps,build} */*/{deps,build}); do
-          ls "${preparedArtifacts}/${d}" | xargs -P 100 -I '##{}##' ln -fs "${preparedArtifacts}/${d}/##{}##" "${d}/##{}##"
-      done
-    popd
+    local linkCandidates=$(mktemp linkCandidatesXXXX.txt)
+    find "${preparedArtifacts}" \
+      '(' -path '*/deps/*.rlib' -or -path '*/deps/*.rmeta' ')' \
+      -printf "%P\n" \
+      >"${linkCandidates}"
 
-    # Keep existing permissions (e.g. exectuable), but also make things writable
-    # since the store is read-only and cargo would otherwise choke
-    chmod -R u+w "${cargoTargetDir}"
+    # Next create any missing directories up front so we can avoid redundant checks later
+    cat "${linkCandidates}" \
+      | xargs --no-run-if-empty -n1 dirname \
+      | sort -u \
+      | (cd "${cargoTargetDir}"; xargs --no-run-if-empty mkdir -p)
 
-    # NB: cargo also doesn't like it if `.cargo-lock` files remain with a
-    # timestamp in the distant past so we need to delete them here
-    find "${cargoTargetDir}" -name '.cargo-lock' -delete
+    # Lastly do the actual symlinking
+    cat "${linkCandidates}" \
+      | xargs -P ${NIX_BUILD_CORES} -I '##{}##' ln -s "${preparedArtifacts}/##{}##" "${cargoTargetDir}/##{}##"
   else
     echo unable to copy cargo artifacts, \"${preparedArtifacts}\" looks invalid
     false

From 7be810ce8a972afa9a22ab8c2ee737aaabe0dcb0 Mon Sep 17 00:00:00 2001
From: Ivan Petkov <ivanppetkov@gmail.com>
Date: Mon, 19 Jun 2023 13:08:06 -0700
Subject: [PATCH 5/7] Update docs and CHANGELOG

---
 CHANGELOG.md | 5 +++++
 docs/API.md  | 1 +
 2 files changed, 6 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1e421390..d19fd454 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 ### Added
 * Added support for the [Trunk](https://trunkrs.dev) wasm app build tool
 
+### Changed
+* `inheritCargoArtifactsHook` will now symlink dependency `.rlib` and `.rmeta`
+  files. This means that derivations which reuse existing cargo artifacts will
+  run faster as fewer files (and bytes!) need to be copied around
+
 ### [0.12.1] - 2023-04-10
 
 ### Changed
diff --git a/docs/API.md b/docs/API.md
index f54f17ec..f343e69a 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -927,6 +927,7 @@ hooks:
 * `configureCargoVendoredDepsHook`
 * `inheritCargoArtifactsHook`
 * `installCargoArtifactsHook`
+* `rsync`
 * `zstd`
 
 ### `craneLib.mkDummySrc`

From 184f52f8d91a65e0bf2f1aa7a9a2194fa9be3e26 Mon Sep 17 00:00:00 2001
From: Ivan Petkov <ivanppetkov@gmail.com>
Date: Mon, 19 Jun 2023 13:08:30 -0700
Subject: [PATCH 6/7] Revert unrelated change

---
 lib/cargoTarpaulin.nix | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/cargoTarpaulin.nix b/lib/cargoTarpaulin.nix
index 1b094f82..5ac007d9 100644
--- a/lib/cargoTarpaulin.nix
+++ b/lib/cargoTarpaulin.nix
@@ -3,7 +3,7 @@
 }:
 
 { cargoExtraArgs ? ""
-, cargoTarpaulinExtraArgs ? "--out Xml --output-dir $out"
+, cargoTarpaulinExtraArgs ? "--skip-clean --out Xml --output-dir $out"
 , ...
 }@origArgs:
 let

From 81a467c1b8c0a32c0f3e284577a76d42580204c8 Mon Sep 17 00:00:00 2001
From: Ivan Petkov <ivanppetkov@gmail.com>
Date: Mon, 19 Jun 2023 14:43:50 -0700
Subject: [PATCH 7/7] cargoTarpaulin: do not clean by default

---
 CHANGELOG.md           | 2 ++
 docs/API.md            | 2 +-
 lib/cargoTarpaulin.nix | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4b77b462..d3857867 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 * `inheritCargoArtifactsHook` will now symlink dependency `.rlib` and `.rmeta`
   files. This means that derivations which reuse existing cargo artifacts will
   run faster as fewer files (and bytes!) need to be copied around
+* `cargoTarpaulin`'s default `cargoTarpaulinExtraArgs` no longer include
+  `--skip-clean`
 
 ### Changed
 * **Breaking**: dropped compatibility for Nix versions below 2.13.3
diff --git a/docs/API.md b/docs/API.md
index 50504652..c5877d05 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -622,7 +622,7 @@ Except where noted below, all derivation attributes are delegated to
   - Default value: `""`
 * `cargoTarpaulinExtraArgs`: additional flags to be passed in the cargo
   tarpaulin invocation
-  - Default value: `"--skip-clean --out Xml --output-dir $out"`
+  - Default value: `"--out Xml --output-dir $out"`
 
 #### Native build dependencies
 The `cargo-tarpaulin` package is automatically appended as a native build input to any
diff --git a/lib/cargoTarpaulin.nix b/lib/cargoTarpaulin.nix
index 5ac007d9..1b094f82 100644
--- a/lib/cargoTarpaulin.nix
+++ b/lib/cargoTarpaulin.nix
@@ -3,7 +3,7 @@
 }:
 
 { cargoExtraArgs ? ""
-, cargoTarpaulinExtraArgs ? "--skip-clean --out Xml --output-dir $out"
+, cargoTarpaulinExtraArgs ? "--out Xml --output-dir $out"
 , ...
 }@origArgs:
 let