lib: find python checks order changed on windows (#2872)

These changes favor py launcher over other checks excluding command line
or npm configuration and environment variable checks.

Also, updated supported python versions list.

Fixes: https://github.com/nodejs/node-gyp/issues/2871

lib/find-python.js

@@ -14,7 +14,7 @@ const programFiles = process.env.ProgramW6432 || process.env.ProgramFiles || `${
 const programFilesX86 = process.env['ProgramFiles(x86)'] || `${programFiles} (x86)`
 
 const winDefaultLocationsArray = []
-for (const majorMinor of ['39', '38', '37', '36']) {
+for (const majorMinor of ['311', '310', '39', '38']) {
   if (foundLocalAppData) {
     winDefaultLocationsArray.push(
       `${localAppData}\\Programs\\Python\\Python${majorMinor}\\python.exe`,
@@ -113,7 +113,20 @@ PythonFinder.prototype = {
           },
           check: this.checkCommand,
           arg: this.env.PYTHON
-        },
+        }
+      ]
+
+      if (this.win) {
+        checks.push({
+          before: () => {
+            this.addLog(
+              'checking if the py launcher can be used to find Python 3')
+          },
+          check: this.checkPyLauncher
+        })
+      }
+
+      checks.push(...[
         {
           before: () => { this.addLog('checking if "python3" can be used') },
           check: this.checkCommand,
@@ -124,7 +137,7 @@ PythonFinder.prototype = {
           check: this.checkCommand,
           arg: 'python'
         }
-      ]
+      ])
 
       if (this.win) {
         for (let i = 0; i < this.winDefaultLocations.length; ++i) {
@@ -138,13 +151,6 @@ PythonFinder.prototype = {
             arg: location
           })
         }
-        checks.push({
-          before: () => {
-            this.addLog(
-              'checking if the py launcher can be used to find Python 3')
-          },
-          check: this.checkPyLauncher
-        })
       }
 
       return checks