Add lambda support to -replace operator

Add support for replacement lambdas when using the -replace operator. Requires minimal changes to existing code by using the following overload: Regex.Replace(string input, MatchEvaluator evaluator) when a ScriptBlock is passed in as the replacement argument.
2026-06-08 12:12:50 +00:00 · 2018-03-14 09:43:57 -07:00
parent 8ffc0b0e3c
commit 915639a177
2 changed files with 94 additions and 10 deletions
@@ -0,0 +1,64 @@
+Describe "Replace Operator" -Tags CI {
+    Context "Replace operator" {
+        It "Replace operator can replace string values using regular expressions" {
+            $res = "Get-Process" -replace "Get", "Stop"
+            $res | Should BeExactly "Stop-Process"
+
+            $res = "image.gif" -replace "\.gif$",".jpg"
+            $res | Should BeExactly "image.jpg"
+        }
+
+        It "Replace operator can be case-insensitive and case-sensitive" {
+            $res = "book" -replace "B","C"
+            $res | Should BeExactly "Cook"
+
+            $res = "book" -ireplace "B","C"
+            $res | Should BeExactly "Cook"
+
+            $res = "book" -creplace "B","C"
+            $res | Should BeExactly "book"
+        }
+
+        It "Replace operator can take 2 arguments, a mandatory pattern, and an optional substitution" {
+            $res = "PowerPoint" -replace "Point","Shell"
+            $res | Should BeExactly "PowerShell"
+
+            $res = "PowerPoint" -replace "Point"
+            $res | Should BeExactly "Power"
+        }
+    }
+
+    Context "Replace operator substitutions" {
+        It "Replace operator supports numbered substitution groups using ```$n" {
+            $res = "domain.example" -replace ".*\.(\w+)$","Tld of '`$0' is - '`$1'"
+            $res | Should BeExactly "Tld of 'domain.example' is - 'example'"
+        }
+
+        It "Replace operator supports named substitution groups using ```${name}" {
+            $res = "domain.example" -replace ".*\.(?<tld>\w+)$","`${tld}"
+            $res | Should BeExactly "example"
+        }
+
+        It "Replace operator can take a ScriptBlock in place of a substitution string" {
+            $res = "ID ABC123" -replace "\b[A-C]+", {return "X" * $args[0].Value.Length}
+            $res | Should BeExactly "ID XXX123"
+        }
+
+        It "Replace operator can take a MatchEvaluator in place of a substitution string" {
+            $matchEvaluator = {return "X" * $args[0].Value.Length} -as [System.Text.RegularExpressions.MatchEvaluator]
+            $res = "ID ABC123" -replace "\b[A-C]+", $matchEvaluator
+            $res | Should BeExactly "ID XXX123"
+        }
+
+        It "Replace operator can take a static PSMethod in place of a substitution string" {
+            class R {
+                static [string] Replace([System.Text.RegularExpressions.Match]$Match) {
+                    return "X" * $Match.Value.Length
+                }
+            }
+            $substitutionMethod = [R]::Replace
+            $res = "ID 0000123" -replace "\b0+", $substitutionMethod
+            $res | Should BeExactly "ID XXXX123"
+        }
+    }
+}