GP-4570 revisions to buildPyPackage task

gradle/debugger/hasPythonPackage.gradle

@@ -30,11 +30,52 @@ def checkPythonVersion(String pyCmd) {
 	}
 }
 
+ext.MIN_PIP_VERSION = [20, 2] // 20.2+
+
+def checkPipVersion(String pyCmd) {
+	try {
+		def stdout = new ByteArrayOutputStream()
+		exec {
+			commandLine pyCmd, "-c", "import pip; print(pip.__version__)"
+			standardOutput = stdout
+			errorOutput = OutputStream.nullOutputStream()
+		}
+		def version = "$stdout".strip();
+		if (version.length() == 0) {
+			println("Warning: python pip not installed (required for build)")
+		}
+		else {
+			println("Found python pip version ${version}")
+			def (majorVer, minorVer) = version.tokenize('.')
+			def major = majorVer.toInteger()
+			def minor = minorVer.toInteger()
+			if (major < MIN_PIP_VERSION[0] || (major == MIN_PIP_VERSION[0] && minor < MIN_PIP_VERSION[1])) {
+				println("Warning: python pip may require upgrade")
+			}
+		}
+		return version
+	}
+	catch (Exception e) {
+		println("Warning: python pip not installed")
+	}
+}
+
 ext.SUPPORTED_PY_VERSIONS = ['3.7', '3.8', '3.9', '3.10', '3.11', '3.12']
 
 def findPython3() {
 	for (pyCmd in ['py', 'python3', 'python']) {
+		def pyVer = checkPythonVersion(pyCmd)
+		if (pyVer in SUPPORTED_PY_VERSIONS) {
+			println("Using python command:  ${pyCmd} (version ${pyVer})")
+			checkPipVersion(pyCmd)
+			return pyCmd
+		}
+	}
+	for (pyVer in SUPPORTED_PY_VERSIONS) {
+		def pyCmd = "python${pyVer}"
 		if (checkPythonVersion(pyCmd) in SUPPORTED_PY_VERSIONS) {
+			println("Using python command:  ${pyCmd}")
+			checkPipVersion(pyCmd)
 			return pyCmd
 		}
 	}
@@ -62,8 +103,6 @@ task assemblePyPackage(type: Copy) {
 	into "build/pypkg/"
 }
 
-rootProject.tasks.prepDev.dependsOn(assemblePyPackage)
-
 task buildPyPackage {
 	ext.dist = { file("build/pypkg/dist") }
 	inputs.files(assemblePyPackage)