installer: don't use 'build' to avoid circular dependencies. (#10729)

Helps with #10717.

dev-python/installer/installer-0.7.0.recipe

@@ -10,7 +10,7 @@ wheels.
 HOMEPAGE="https://pypi.org/project/installer/"
 COPYRIGHT="2020 Pradyun Gedam"
 LICENSE="MIT"
-REVISION="4"
+REVISION="5"
 SOURCE_URI="https://pypi.io/packages/source/i/installer/installer-$portVersion.tar.gz"
 CHECKSUM_SHA256="a26d3e3116289bb08216e0d0f7d925fcef0b0194eedfa0c944bcaaa106c4b631"
 
@@ -27,11 +27,11 @@ BUILD_REQUIRES="
 	haiku_devel
 	"
 
-PYTHON_PACKAGES=(python39 python310)
 PYTHON_VERSIONS=(3.9 3.10)
-for i in "${!PYTHON_PACKAGES[@]}"; do
-	pythonPackage=${PYTHON_PACKAGES[i]}
+
+for i in "${!PYTHON_VERSIONS[@]}"; do
 	pythonVersion=${PYTHON_VERSIONS[$i]}
+	pythonPackage=python${pythonVersion//.}
 
 	eval "PROVIDES_${pythonPackage}=\"
 		${portName}_$pythonPackage = $portVersion
@@ -40,8 +40,8 @@ for i in "${!PYTHON_PACKAGES[@]}"; do
 		haiku
 		cmd:python$pythonVersion
 		\""
+
 	BUILD_REQUIRES+="
-		build_$pythonPackage
 		flit_core_$pythonPackage
 		"
 	BUILD_PREREQUIRES+="
@@ -51,13 +51,21 @@ done
 
 INSTALL()
 {
-	for i in "${!PYTHON_PACKAGES[@]}"; do
-		python=python${PYTHON_VERSIONS[$i]}
+	for i in "${!PYTHON_VERSIONS[@]}"; do
+		pythonVersion=${PYTHON_VERSIONS[$i]}
+		pythonPackage=python${pythonVersion//.}
 
-		$python -m build -wn --skip-dependency-check
+		python=python$pythonVersion
+		installdir=$prefix/lib/$python/vendor-packages
+
+		rm -rf dist
+
+		# We don't use "build" here, to avoid circular depedencies later on.
+
+		$python -m flit_core.wheel
 		PYTHONPATH=src $python -m installer --prefix=$prefix dist/*.whl
 
-		packageEntries ${PYTHON_PACKAGES[i]} \
-			$prefix/lib/python*
+		packageEntries $pythonPackage \
+			$prefix/lib/$python
 	done
 }