[POWERSHELL] fix: single-quote DTO property names to prevent $-variable interpolation

PowerShell treats `$` inside double-quoted strings as the sigil for variable
interpolation, so `"$foo" = ${Foo}` inside a hash literal becomes `<value-of-$foo> = <value-of-Foo>`.
When an OpenAPI property name starts with (or contains) `$` — e.g. `$type` from
C# polymorphic payloads or `$ref` / `$schema` from JSON Schema — the generated
Initialize- and ConvertFrom- commandlets emit invalid PSCustomObject hash keys
and empty regex patterns, breaking DTO (de)serialization.

Swap all user-property-name emissions in `model_simple.mustache` from
double-quoted to single-quoted literals so baseName is preserved verbatim:

- `$PSO = [PSCustomObject]@{ '<baseName>' = ${<name>} }` (3 sites)
- `$AllProperties = ('<baseName>', ...)` (1 site)
- `-match '<baseName>'` and `.Properties['<baseName>']` (4 sites)

Fixes: #23535
Co-Authored-By: Claude <noreply@anthropic.com>

Author: gaurav0107

modules/openapi-generator/src/main/resources/powershell/model_simple.mustache

@@ -122,7 +122,7 @@ function Initialize-{{{apiNamePrefix}}}{{{classname}}} {
         $PSO = [PSCustomObject]@{
             {{=<< >>=}}
             <<#allVars>>
-            "<<baseName>>" = ${<<name>>}
+            '<<baseName>>' = ${<<name>>}
             <</allVars>>
             <<={{ }}=>>
         }
@@ -184,7 +184,7 @@ function Initialize-{{{apiNamePrefix}}}{{{classname}}} {
             {{=<< >>=}}
             <<#allVars>>
             <<^isReadOnly>>
-            "<<baseName>>" = ${<<name>>}
+            '<<baseName>>' = ${<<name>>}
             <</isReadOnly>>
             <</allVars>>
             <<={{ }}=>>
@@ -228,7 +228,7 @@ function ConvertFrom-{{{apiNamePrefix}}}JsonTo{{{classname}}} {
         {{/isAdditionalPropertiesTrue}}
 
         # check if Json contains properties not defined in {{{apiNamePrefix}}}{{{classname}}}
-        $AllProperties = ({{#allVars}}"{{{baseName}}}"{{^-last}}, {{/-last}}{{/allVars}})
+        $AllProperties = ({{#allVars}}'{{{baseName}}}'{{^-last}}, {{/-last}}{{/allVars}})
         foreach ($name in $JsonParameters.PsObject.Properties.Name) {
             {{^isAdditionalPropertiesTrue}}
             if (!($AllProperties.Contains($name))) {
@@ -250,29 +250,29 @@ function ConvertFrom-{{{apiNamePrefix}}}JsonTo{{{classname}}} {
         }
 
         {{/-first}}
-        if (!([bool]($JsonParameters.PSobject.Properties.name -match "{{{baseName}}}"))) {
+        if (!([bool]($JsonParameters.PSobject.Properties.name -match '{{{baseName}}}'))) {
             throw "Error! JSON cannot be serialized due to the required property '{{{baseName}}}' missing."
         } else {
-            ${{name}} = $JsonParameters.PSobject.Properties["{{{baseName}}}"].value
+            ${{name}} = $JsonParameters.PSobject.Properties['{{{baseName}}}'].value
         }
 
         {{/requiredVars}}
         {{#optionalVars}}
-        if (!([bool]($JsonParameters.PSobject.Properties.name -match "{{{baseName}}}"))) { #optional property not found
+        if (!([bool]($JsonParameters.PSobject.Properties.name -match '{{{baseName}}}'))) { #optional property not found
             ${{name}} = $null
         } else {
-            ${{name}} = $JsonParameters.PSobject.Properties["{{{baseName}}}"].value
+            ${{name}} = $JsonParameters.PSobject.Properties['{{{baseName}}}'].value
         }
 
         {{/optionalVars}}
         $PSO = [PSCustomObject]@{
             {{=<< >>=}}
             <<#allVars>>
-            "<<baseName>>" = ${<<name>>}
+            '<<baseName>>' = ${<<name>>}
             <</allVars>>
             <<={{ }}=>>
             {{#isAdditionalPropertiesTrue}}
-            "AdditionalProperties" = ${{{apiNamePrefix}}}{{{classname}}}AdditionalProperties
+            'AdditionalProperties' = ${{{apiNamePrefix}}}{{{classname}}}AdditionalProperties
             {{/isAdditionalPropertiesTrue}}
         }
 

modules/openapi-generator/src/test/java/org/openapitools/codegen/powershell/PowerShellClientCodegenTest.java

@@ -0,0 +1,86 @@
+/*
+ * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ * Copyright 2018 SmartBear Software
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.openapitools.codegen.powershell;
+
+import io.swagger.parser.OpenAPIParser;
+import io.swagger.v3.oas.models.OpenAPI;
+import io.swagger.v3.parser.core.models.ParseOptions;
+import org.openapitools.codegen.ClientOptInput;
+import org.openapitools.codegen.CodegenConstants;
+import org.openapitools.codegen.DefaultGenerator;
+import org.openapitools.codegen.languages.PowerShellClientCodegen;
+import org.testng.annotations.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+
+import static org.openapitools.codegen.TestUtils.assertFileContains;
+import static org.openapitools.codegen.TestUtils.assertFileNotContains;
+
+public class PowerShellClientCodegenTest {
+
+    /**
+     * Regression test for <a href="https://github.com/OpenAPITools/openapi-generator/issues/23535">#23535</a>.
+     *
+     * PowerShell treats {@code $} inside double-quoted strings as the sigil for
+     * variable interpolation, so hash-table keys emitted as {@code "$foo"} get
+     * rewritten at runtime to the value of {@code $foo} (usually empty). This
+     * produces invalid DTO commandlets whenever an OpenAPI property name starts
+     * with (or contains) {@code $}. The {@code model_simple.mustache} template
+     * now emits single-quoted keys so the literal baseName is preserved.
+     */
+    @Test
+    public void dollarSignPropertyNamesAreSingleQuoted() throws IOException {
+        File output = Files.createTempDirectory("test-powershell-23535").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        OpenAPI openAPI = new OpenAPIParser()
+                .readLocation("src/test/resources/3_0/dollar-in-names-pull14359.yaml", null, new ParseOptions())
+                .getOpenAPI();
+
+        PowerShellClientCodegen codegen = new PowerShellClientCodegen();
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        ClientOptInput input = new ClientOptInput();
+        input.openAPI(openAPI);
+        input.config(codegen);
+
+        DefaultGenerator generator = new DefaultGenerator();
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODELS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_TESTS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_DOCS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.APIS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.SUPPORTING_FILES, "false");
+        generator.opts(input).generate();
+
+        // The PowerShell codegen sanitises "$DollarModel$" to "DollarModel",
+        // so the emitted model lives at src/<package>/Model/DollarModel.ps1.
+        java.nio.file.Path dollarModelPs1 = Paths.get(outputPath + "/src/PSOpenAPITools/Model/DollarModel.ps1");
+
+        // Property names containing `$` must be single-quoted so PowerShell does
+        // not attempt variable interpolation.
+        assertFileContains(dollarModelPs1, "'$dollarValue$'");
+
+        // The previous double-quoted emission must no longer appear anywhere in
+        // the generated model file.
+        assertFileNotContains(dollarModelPs1, "\"$dollarValue$\" = ");
+    }
+}