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Optimize IEnumerable variant of replace operator (#14221)

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Ilya 2020-12-10 00:46:27 +05:00 committed by GitHub
parent 971c428769
commit ba49eb225f
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2 changed files with 70 additions and 25 deletions
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77
src/System.Management.Automation/engine/lang/parserutils.cs
View file

@ -965,6 +965,7 @@ namespace System.Management.Automation
}
}
var replacer = ReplaceOperatorImpl.Create(context, rr, substitute);
IEnumerator list = LanguagePrimitives.GetEnumerator(lval);
if (list == null)
{
@ -978,7 +979,7 @@ namespace System.Management.Automation
lvalString = lval?.ToString() ?? string.Empty;
}
return ReplaceOperatorImpl(context, lvalString, rr, substitute);
return replacer.Replace(lvalString);
}
else
{
@ -986,45 +987,55 @@ namespace System.Management.Automation
while (ParserOps.MoveNext(context, errorPosition, list))
{
string lvalString = PSObject.ToStringParser(context, ParserOps.Current(errorPosition, list));
resultList.Add(ReplaceOperatorImpl(context, lvalString, rr, substitute));
resultList.Add(replacer.Replace(lvalString));
}
return resultList.ToArray();
}
}
/// <summary>
/// ReplaceOperator implementation.
/// Abstracts away conversion of the optional substitute parameter to either a string or a MatchEvaluator delegate
/// and finally returns the result of the final Regex.Replace operation.
/// </summary>
/// <param name="context">The execution context in which to evaluate the expression.</param>
/// <param name="input">The input string.</param>
/// <param name="regex">A Regex instance.</param>
/// <param name="substitute">The substitute value.</param>
/// <returns>The result of the regex.Replace operation.</returns>
private static object ReplaceOperatorImpl(ExecutionContext context, string input, Regex regex, object substitute)
private struct ReplaceOperatorImpl
{
switch (substitute)
public static ReplaceOperatorImpl Create(ExecutionContext context, Regex regex, object substitute)
{
case string replacementString:
return regex.Replace(input, replacementString);
return new ReplaceOperatorImpl(context, regex, substitute);
}
case ScriptBlock sb:
MatchEvaluator me = GetMatchEvaluator(context, sb);
return regex.Replace(input, me);
private readonly Regex _regex;
private readonly string _cachedReplacementString;
private readonly MatchEvaluator _cachedMatchEvaluator;
case object val when LanguagePrimitives.TryConvertTo(val, out MatchEvaluator matchEvaluator):
return regex.Replace(input, matchEvaluator);
private ReplaceOperatorImpl(
ExecutionContext context,
Regex regex,
object substitute)
{
_regex = regex;
_cachedReplacementString = null;
_cachedMatchEvaluator = null;
default:
string replacement = PSObject.ToStringParser(context, substitute);
return regex.Replace(input, replacement);
switch (substitute)
{
case string replacement:
_cachedReplacementString = replacement;
break;
case ScriptBlock sb:
_cachedMatchEvaluator = GetMatchEvaluator(context, sb);
break;
case object val when LanguagePrimitives.TryConvertTo(val, out _cachedMatchEvaluator):
break;
default:
_cachedReplacementString = PSObject.ToStringParser(context, substitute);
break;
}
}
// Local helper function to avoid creating an instance of the generated delegate helper class
// every time 'ReplaceOperatorImpl' is invoked.
static MatchEvaluator GetMatchEvaluator(ExecutionContext context, ScriptBlock sb)
private static MatchEvaluator GetMatchEvaluator(ExecutionContext context, ScriptBlock sb)
{
return match =>
{
@ -1039,6 +1050,22 @@ namespace System.Management.Automation
return PSObject.ToStringParser(context, result);
};
}
/// <summary>
/// ReplaceOperator implementation.
/// Abstracts away conversion of the optional substitute parameter to either a string or a MatchEvaluator delegate
/// and finally returns the result of the final Regex.Replace operation.
/// </summary>
public object Replace(string input)
{
if (_cachedReplacementString is not null)
{
return _regex.Replace(input, _cachedReplacementString);
}
Dbg.Assert(_cachedMatchEvaluator is not null, "_cachedMatchEvaluator should be not null when code reach here.");
return _regex.Replace(input, _cachedMatchEvaluator);
}
}
/// <summary>

18
test/powershell/Language/Operators/ReplaceOperator.Tests.ps1
View file

@ -11,6 +11,12 @@ Describe "Replace Operator" -Tags CI {
$res | Should -BeExactly "image.jpg"
}
It "Replace operator can convert an substitution object to string" {
$substitution = Get-Process -Id $pid
$res = "!3!" -replace "3",$substitution
$res | Should -BeExactly "!System.Diagnostics.Process (pwsh)!"
}
It "Replace operator can be case-insensitive and case-sensitive" {
$res = "book" -replace "B","C"
$res | Should -BeExactly "Cook"
@ -29,6 +35,18 @@ Describe "Replace Operator" -Tags CI {
$res = "PowerPoint" -replace "Point"
$res | Should -BeExactly "Power"
}
It "Replace operator can take an enumerable as first argument, a mandatory pattern, and an optional substitution" {
$res = "PowerPoint1","PowerPoint2" -replace "Point","Shell"
$res.Count | Should -Be 2
$res[0] | Should -BeExactly "PowerShell1"
$res[1] | Should -BeExactly "PowerShell2"
$res = "PowerPoint1","PowerPoint2" -replace "Point"
$res.Count | Should -Be 2
$res[0] | Should -BeExactly "Power1"
$res[1] | Should -BeExactly "Power2"
}
}
Context "Replace operator substitutions" {