feat: Add flit-core support

Signed-off-by: Pascal Zimmermann <pascal.zimmermann@theiotstudio.com>

Author: ZPascal

README.md

@@ -24,7 +24,9 @@ To build this buildpack, run the following commands from the buildpack's directo
 1. Install buildpack-packager
 
     ```bash
-    go install github.com/cloudfoundry/libbuildpack/packager/buildpack-packager
+    go get github.com/cloudfoundry/libbuildpack
+    cd ~/go/src/github.com/cloudfoundry/libbuildpack && GO111MODULE=on go mod download
+    cd packager/buildpack-packager &&  GO111MODULE=on go install
     ```
 
 1. Build the buildpack

go.mod

@@ -5,7 +5,7 @@ go 1.24.0
 require (
 	github.com/Dynatrace/libbuildpack-dynatrace v1.8.0
 	github.com/blang/semver v3.5.1+incompatible
-	github.com/cloudfoundry/libbuildpack v0.0.0-20260306121953-8ab9253c8181
+	github.com/cloudfoundry/libbuildpack v0.0.0-20260306125332-dcaf55eb6f33
 	github.com/cloudfoundry/switchblade v0.9.4
 	github.com/golang/mock v1.6.0
 	github.com/kr/text v0.2.0

go.sum

@@ -748,6 +748,8 @@ github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDk
 github.com/cloudflare/circl v1.1.0/go.mod h1:prBCrKB9DV4poKZY1l9zBXg2QJY7mvgRvtMxxK7fi4I=
 github.com/cloudfoundry/libbuildpack v0.0.0-20260306121953-8ab9253c8181 h1:di63teVid/uT+6TAqBSXFqxNM3sAbxk6hssYppZBvbw=
 github.com/cloudfoundry/libbuildpack v0.0.0-20260306121953-8ab9253c8181/go.mod h1:Qtj1XicpoDn88w2cvVCYtw1Whq+kK3bouin0xNZ9lIU=
+github.com/cloudfoundry/libbuildpack v0.0.0-20260306125332-dcaf55eb6f33 h1:O3uSzqYH1x5yK/awqNJiwcxohLHfPkXO4KOgVHgCg4o=
+github.com/cloudfoundry/libbuildpack v0.0.0-20260306125332-dcaf55eb6f33/go.mod h1:Qtj1XicpoDn88w2cvVCYtw1Whq+kK3bouin0xNZ9lIU=
 github.com/cloudfoundry/switchblade v0.9.4 h1:93O90a/DRRcZ4h50htDh4z7+FMliqy/lQH6IFgVa+mQ=
 github.com/cloudfoundry/switchblade v0.9.4/go.mod h1:hIEQdGAsuNnzlyQfsD5OIORt38weSBar6Wq5/JX6Omo=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=

manifest.yml

@@ -209,6 +209,15 @@ dependencies:
   - cflinuxfs4
   source: https://files.pythonhosted.org/packages/86/ff/f75651350db3cf2ef767371307eb163f3cc1ac03e16fdf3ac347607f7edb/setuptools-80.10.1.tar.gz
   source_sha256: bf2e513eb8144c3298a3bd28ab1a5edb739131ec5c22e045ff93cd7f5319703a
+- name: flit-core
+  version: 3.12.0
+  uri: https://buildpacks.cloudfoundry.org/dependencies/flit_core/flit_core-3.12.0_linux_noarch_any-stack_e8745ea3.tgz
+  sha256: e8745ea31b2af10b2056552a65181b52f8fcc645f1ac13a4f6440525fcc896d1
+  cf_stacks:
+    - cflinuxfs4
+    - cflinuxfs3
+  source: https://files.pythonhosted.org/packages/69/59/b6fc2188dfc7ea4f936cd12b49d707f66a1cb7a1d2c16172963534db741b/flit_core-3.12.0.tar.gz
+  source_sha256: 18f63100d6f94385c6ed57a72073443e1a71a4acb4339491615d0f16d6ff01b2
 include_files:
 - CHANGELOG
 - CONTRIBUTING.md

src/python/supply/supply.go

@@ -743,7 +743,7 @@ func (s *Supplier) RunPipVendored() error {
 // dependencies - wheel and setuptools. These are packaged by the dependency
 // pipeline within the "pip" dependency.
 func (s *Supplier) InstallCommonBuildDependencies() error {
-	var commonDeps = []string{"wheel", "setuptools"}
+	var commonDeps = []string{"wheel", "setuptools", "flit-core"}
 	tempPath := filepath.Join("/tmp", "common_build_deps")
 	if err := s.Installer.InstallOnlyVersion("pip", tempPath); err != nil {
 		return err

src/python/supply/supply_test.go

@@ -633,10 +633,11 @@ MarkupSafe==2.0.1
 
 	Describe("InstallCommonBuildDependencies", func() {
 		Context("successful installation", func() {
-			It("runs command to install wheel and setuptools", func() {
+			It("runs command to install wheel, setuptools and flit-core", func() {
 				mockInstaller.EXPECT().InstallOnlyVersion("pip", "/tmp/common_build_deps")
 				mockCommand.EXPECT().Execute(buildDir, gomock.Any(), gomock.Any(), "python", "-m", "pip", "install", "wheel", "--no-index", "--upgrade-strategy=only-if-needed", "--find-links=/tmp/common_build_deps")
 				mockCommand.EXPECT().Execute(buildDir, gomock.Any(), gomock.Any(), "python", "-m", "pip", "install", "setuptools", "--no-index", "--upgrade-strategy=only-if-needed", "--find-links=/tmp/common_build_deps")
+				mockCommand.EXPECT().Execute(buildDir, gomock.Any(), gomock.Any(), "python", "-m", "pip", "install", "flit-core", "--no-index", "--upgrade-strategy=only-if-needed", "--find-links=/tmp/common_build_deps")
 
 				Expect(supplier.InstallCommonBuildDependencies()).To(Succeed())
 			})