feat: Add poetry-core support

# Conflicts:
#	src/python/supply/supply_test.go

Author: ZPascal

src/python/supply/supply.go

@@ -764,6 +764,15 @@ func (s *Supplier) InstallCommonBuildDependencies() error {
 			return fmt.Errorf("could not install build-time dependency %s: %v", dep, err)
 		}
 	}
+
+	if err := s.Installer.InstallOnlyVersion("poetry-core", tempPath); err != nil {
+		return fmt.Errorf("could not prepare build-time dependency poetry-core: %v", err)
+	}
+	s.Log.Info("Installing build-time dependency poetry-core (bootstrap)")
+	if err := s.runPipInstall(tempPath, "--no-build-isolation"); err != nil {
+		return fmt.Errorf("could not bootstrap-install poetry-core: %v", err)
+	}
+
 	return nil
 }
 

src/python/supply/supply_test.go

@@ -662,6 +662,27 @@ MarkupSafe==2.0.1
 				Expect(supplier.InstallCommonBuildDependencies()).To(MatchError("could not install build-time dependency wheel: some-pip-error"))
 			})
 		})
+
+		Context("poetry-core preparation fails", func() {
+			It("returns a useful error message", 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")
+				mockInstaller.EXPECT().InstallOnlyVersion("poetry-core", "/tmp/common_build_deps").Return(fmt.Errorf("prepare-error"))
+				Expect(supplier.InstallCommonBuildDependencies()).To(MatchError("could not prepare build-time dependency poetry-core: prepare-error"))
+			})
+		})
+
+		Context("poetry-core bootstrap fails", func() {
+			It("returns a useful error message", 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")
+				mockInstaller.EXPECT().InstallOnlyVersion("poetry-core", "/tmp/common_build_deps")
+				mockCommand.EXPECT().Execute(buildDir, gomock.Any(), gomock.Any(), "python", "-m", "pip", "install", "/tmp/common_build_deps", "--no-build-isolation").Return(fmt.Errorf("poetry-error"))
+				Expect(supplier.InstallCommonBuildDependencies()).To(MatchError("could not bootstrap-install poetry-core: poetry-error"))
+			})
+		})
 	})
 
 	Describe("CreateDefaultEnv", func() {