Fixed Python 3.8 directory discovery (#217)

images/build/Dockerfile

@@ -298,13 +298,16 @@ RUN . /tmp/__python-versions.sh && set -ex \
  && [ -d "/opt/python/$PYTHON27_VERSION" ] && echo /opt/python/$PYTHON27_VERSION/lib >> /etc/ld.so.conf.d/python.conf \
  && [ -d "/opt/python/$PYTHON36_VERSION" ] && echo /opt/python/$PYTHON36_VERSION/lib >> /etc/ld.so.conf.d/python.conf \
  && [ -d "/opt/python/$PYTHON37_VERSION" ] && echo /opt/python/$PYTHON37_VERSION/lib >> /etc/ld.so.conf.d/python.conf \
+ && [ -d "/opt/python/$PYTHON38_VERSION" ] && echo /opt/python/$PYTHON38_VERSION/lib >> /etc/ld.so.conf.d/python.conf \
  && ldconfig
+# The link from PYTHON38_VERSION to 3.8.0 exists because "3.8.0b1" isn't a valid SemVer string.
 RUN . /tmp/__python-versions.sh && set -ex \
  && ln -s $PYTHON27_VERSION /opt/python/2.7 \
  && ln -s 2.7 /opt/python/2 \
  && ln -s $PYTHON36_VERSION /opt/python/3.6 \
  && ln -s $PYTHON37_VERSION /opt/python/latest \
  && ln -s $PYTHON37_VERSION /opt/python/3.7 \
+ && ln -s $PYTHON38_VERSION /opt/python/3.8.0 \
  && ln -s $PYTHON38_VERSION /opt/python/3.8 \
  && ln -s 3.7 /opt/python/3
 RUN set -ex \

src/BuildScriptGenerator/VersionProviderHelpers.cs

@@ -2,6 +2,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT license.
 // --------------------------------------------------------------------------------------------
+
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -22,10 +23,8 @@ namespace Microsoft.Oryx.BuildScriptGenerator
             IEnumerable<DirectoryInfo> versionDirectories;
             try
             {
-                versionDirectories = Directory.EnumerateDirectories(
-                    versionsDir,
-                    "*",
-                    listOptions).Select(versionDir => new DirectoryInfo(versionDir));
+                versionDirectories = Directory.EnumerateDirectories(versionsDir, "*", listOptions)
+                    .Select(versionDir => new DirectoryInfo(versionDir));
             }
             catch (IOException)
             {

src/BuildScriptGeneratorCli/Commands/BuildCommand.cs

@@ -19,7 +19,7 @@ using Microsoft.Oryx.Common;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(BuildCommand.Name, Description = "Build an app.")]
+    [Command(Name, Description = "Build an app.")]
     internal class BuildCommand : CommandBase
     {
         public const string Name = "build";

src/BuildScriptGeneratorCli/Commands/BuildScriptCommand.cs

@@ -13,7 +13,7 @@ using Microsoft.Oryx.Common;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(BuildScriptCommand.Name, Description = "Generate build script to standard output.")]
+    [Command(Name, Description = "Generate build script to standard output.")]
     internal class BuildScriptCommand : CommandBase
     {
         public const string Name = "build-script";

src/BuildScriptGeneratorCli/Commands/BuildpackBuildCommand.cs

@@ -11,8 +11,7 @@ using Microsoft.Extensions.Logging;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(BuildpackBuildCommand.Name, Description = "Build an app in the current working directory " +
-        "(for use in a Buildpack).")]
+    [Command(Name, Description = "Build an app in the current working directory (for use in a Buildpack).")]
     internal class BuildpackBuildCommand : BuildCommand
     {
         public new const string Name = "buildpack-build";

src/BuildScriptGeneratorCli/Commands/BuildpackDetectCommand.cs

@@ -15,8 +15,8 @@ using Microsoft.Oryx.Common;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(BuildpackDetectCommand.Name, Description = "Determine whether Oryx can be applied as a buildpack to " +
-        "an app in the current working directory.")]
+    [Command(Name, Description = "Determine whether Oryx can be applied as a buildpack to an app in the current " +
+        "working directory.")]
     internal class BuildpackDetectCommand : CommandBase
     {
         public const string Name = "buildpack-detect";

src/BuildScriptGeneratorCli/Commands/InstallRunTimeCommand.cs

@@ -12,7 +12,7 @@ using Microsoft.Oryx.Common;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(InstallRunTimeCommand.Name, Description = "Install the required runtime components for a platform.")]
+    [Command(Name, Description = "Install the required runtime components for a platform.")]
     internal class InstallRunTimeCommand : CommandBase
     {
         public const string Name = "install-runtime";

src/BuildScriptGeneratorCli/Commands/LanguagesCommand.cs

@@ -16,8 +16,7 @@ using Newtonsoft.Json;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(LanguagesCommand.Name, Description = "Show the list of supported platforms and other information " +
-        "like versions, properties etc.")]
+    [Command(Name, Description = "Show a list of supported platforms along with their versions and build properties.")]
     internal class LanguagesCommand : CommandBase
     {
         public const string Name = "languages";

src/BuildScriptGeneratorCli/Commands/RunScriptCommand.cs

@@ -13,7 +13,7 @@ using Microsoft.Oryx.Common;
 
 namespace Microsoft.Oryx.BuildScriptGeneratorCli
 {
-    [Command(RunScriptCommand.Name, Description = "Generate startup script.",
+    [Command(Name, Description = "Generate startup script.",
         ThrowOnUnexpectedArgument = false, AllowArgumentSeparator = true)]
     internal class RunScriptCommand : CommandBase
     {