Guard the 'clean' block behind an experimental feature

PowerShell · Oct 11, 2021 · 93305d4 · 93305d4
1 parent 535584c
commit 93305d4
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Showing 2 changed files with 12 additions and 0 deletions.
diff --git a/src/System.Management.Automation/engine/ExperimentalFeature/ExperimentalFeature.cs b/src/System.Management.Automation/engine/ExperimentalFeature/ExperimentalFeature.cs
@@ -23,6 +23,7 @@ public class ExperimentalFeature
         internal const string EngineSource = "PSEngine";
         internal const string PSNativeCommandArgumentPassingFeatureName = "PSNativeCommandArgumentPassing";
         internal const string PSNativeCommandErrorActionPreferenceFeatureName = "PSNativeCommandErrorActionPreference";
+        internal const string PSCleanBlockFeatureName = "PSCleanBlock";
 
         #endregion
 
@@ -126,6 +127,9 @@ static ExperimentalFeature()
                 new ExperimentalFeature(
                     name: PSNativeCommandErrorActionPreferenceFeatureName,
                     description: "Native commands with non-zero exit codes issue errors according to $ErrorActionPreference when $PSNativeCommandUseErrorActionPreference is $true"),
+                new ExperimentalFeature(
+                    name: PSCleanBlockFeatureName,
+                    description: "Add support of a 'Clean' block to functions and script cmdlets for easy resource cleanup"),
             };
 
             EngineExperimentalFeatures = new ReadOnlyCollection<ExperimentalFeature>(engineFeatures);

diff --git a/src/System.Management.Automation/engine/parser/tokenizer.cs b/src/System.Management.Automation/engine/parser/tokenizer.cs
@@ -699,8 +699,16 @@ static Tokenizer()
             Diagnostics.Assert(s_keywordText.Length == s_keywordTokenKind.Length, "Keyword table sizes must match");
             Diagnostics.Assert(_operatorText.Length == s_operatorTokenKind.Length, "Operator table sizes must match");
 
+            bool isCleanBlockFeatureEnabled = ExperimentalFeature.IsEnabled(ExperimentalFeature.PSCleanBlockFeatureName);
+
             for (int i = 0; i < s_keywordText.Length; ++i)
             {
+                if (!isCleanBlockFeatureEnabled && s_keywordText[i] == "clean")
+                {
+                    // Skip adding the 'clean' keyword when the feature is disabled.
+                    continue;
+                }
+
                 s_keywordTable.Add(s_keywordText[i], s_keywordTokenKind[i]);
             }