[csharp][generichost] Implement not required nullable properties (#16810)

* init

* fixed read and write

* completed changes using latest-nrt sample

* fixed all samples

* add null check on write, change on exception

* resolved conflicts

* build samples

* added backing property for not required properties

* more not required and nullable hanlding improvements

* revert sample updates for a merge master

* revert sample updates for a merge master

* sample build is working, need to remove warnings

* fixed warnings in .net 7 with nrt

* fixed manual tests

* fixed all samples

* fix npe

* removed debugging lines

* revert changes to unused file

* removed unused lambdas

* fix a serialization bug

* make option a hidden property

* updated documentation

* improved parameter ordering

Author: devhl-labs

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractCSharpCodegen.java

@@ -418,21 +418,28 @@ public void execute(Template.Fragment fragment, Writer writer) throws IOExceptio
 
     @Override
     protected ImmutableMap.Builder<String, Lambda> addMustacheLambdas() {
+        CopyLambda copyLambda = new CopyLambda();
+
         return super.addMustacheLambdas()
                 .put("camelcase_param", new CamelCaseLambda().generator(this).escapeAsParamName(true))
                 .put("required", new RequiredParameterLambda())
                 .put("optional", new OptionalParameterLambda().generator(this))
                 .put("joinWithComma", new JoinWithCommaLambda())
+                .put("joinWithAmpersand", new JoinWithCommaLambda(true, "  ", " && "))
                 .put("joinLinesWithComma", new JoinWithCommaLambda(false, "\n", ",\n"))
                 .put("joinConditions", new JoinWithCommaLambda(true, "  ", " && "))
                 .put("trimLineBreaks", new TrimLineBreaksLambda())
                 .put("trimTrailingWithNewLine", new TrimTrailingWhiteSpaceLambda(true))
                 .put("trimTrailing", new TrimTrailingWhiteSpaceLambda(false))
                 .put("first", new FirstLambda("  "))
                 .put("firstDot", new FirstLambda("\\."))
+                .put("indent1", new IndentedLambda(4, " ", false, true))
                 .put("indent3", new IndentedLambda(12, " ", false, true))
                 .put("indent4", new IndentedLambda(16, " ", false, true))
-                .put("uniqueLinesWithNewLine", new UniqueLambda("\n", true));
+                .put("copy", copyLambda)
+                .put("paste", new PasteLambda(copyLambda, true, true, true, false))
+                .put("pasteOnce", new PasteLambda(copyLambda, true, true, true, true))
+                .put("pasteLine", new PasteLambda(copyLambda, true, true, false, false));
     }
 
     @Override

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java

@@ -454,14 +454,13 @@ public CodegenModel fromModel(String name, Schema model) {
             Collections.sort(codegenModel.readWriteVars, propertyComparatorByName);
             Collections.sort(codegenModel.parentVars, propertyComparatorByName);
 
-            Comparator<CodegenProperty> comparator = propertyComparatorByNullable.thenComparing(propertyComparatorByDefaultValue);
-            Collections.sort(codegenModel.vars, comparator);
-            Collections.sort(codegenModel.allVars, comparator);
-            Collections.sort(codegenModel.requiredVars, comparator);
-            Collections.sort(codegenModel.optionalVars, comparator);
-            Collections.sort(codegenModel.readOnlyVars, comparator);
-            Collections.sort(codegenModel.readWriteVars, comparator);
-            Collections.sort(codegenModel.parentVars, comparator);
+            Collections.sort(codegenModel.vars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.allVars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.requiredVars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.optionalVars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.readOnlyVars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.readWriteVars, propertyComparatorByNotNullableRequiredNoDefault);
+            Collections.sort(codegenModel.parentVars, propertyComparatorByNotNullableRequiredNoDefault);
         }
 
         return codegenModel;
@@ -474,24 +473,12 @@ public int compare(CodegenProperty one, CodegenProperty another) {
         }
     };
 
-    public static Comparator<CodegenProperty> propertyComparatorByDefaultValue = new Comparator<CodegenProperty>() {
+    public static Comparator<CodegenProperty> propertyComparatorByNotNullableRequiredNoDefault = new Comparator<CodegenProperty>() {
         @Override
         public int compare(CodegenProperty one, CodegenProperty another) {
-            if ((one.defaultValue == null) == (another.defaultValue == null))
-                return 0;
-            else if (one.defaultValue == null)
-                return -1;
-            else
-                return 1;
-        }
-    };
-
-    public static Comparator<CodegenProperty> propertyComparatorByNullable = new Comparator<CodegenProperty>() {
-        @Override
-        public int compare(CodegenProperty one, CodegenProperty another) {
-            if (one.isNullable == another.isNullable)
+            if (one.isNullable == another.isNullable && one.required == another.required && (one.defaultValue == null) == (another.defaultValue == null))
                 return 0;
-            else if (Boolean.FALSE.equals(one.isNullable))
+            else if (!one.isNullable && one.required && one.defaultValue == null)
                 return -1;
             else
                 return 1;

modules/openapi-generator/src/main/java/org/openapitools/codegen/templating/mustache/CopyLambda.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ *
+ * 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.templating.mustache;
+
+import java.io.IOException;
+import java.io.Writer;
+
+import com.samskivert.mustache.Mustache;
+import com.samskivert.mustache.Template.Fragment;
+
+/**
+ * Saves template text to be used later.
+ *
+ * Register:
+ * <pre>
+ * additionalProperties.put("copy", new CopyLambda());
+ * </pre>
+ *
+ * Use:
+ * <pre>
+ * {{#copy}}{{name}}{{/copy}}
+ * </pre>
+ */
+public class CopyLambda implements Mustache.Lambda {
+    public String savedContent;
+
+    public CopyLambda() {
+    }
+
+    @Override
+    public void execute(Fragment fragment, Writer writer) throws IOException {
+        savedContent = fragment.execute().stripTrailing();
+    }
+}

modules/openapi-generator/src/main/java/org/openapitools/codegen/templating/mustache/PasteLambda.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2018 OpenAPI-Generator Contributors (https://openapi-generator.tech)
+ *
+ * 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.templating.mustache;
+
+import java.io.IOException;
+import java.io.Writer;
+
+import com.samskivert.mustache.Mustache;
+import com.samskivert.mustache.Template.Fragment;
+
+/**
+ * Writes text that was previously saved.
+ *
+ * Register:
+ * <pre>
+ * additionalProperties.put("paste", new PasteLambda(copyLambda, true, true, true, false));
+ * </pre>
+ *
+ * Use:
+ * <pre>
+ * {{#paste}}{{/paste}}
+ * </pre>
+ */
+public class PasteLambda implements Mustache.Lambda {
+    private final CopyLambda copyLambda;
+    private final Boolean stripLeading;
+    private final Boolean stripTrailing;
+    private final Boolean endWithLineBreak;
+    private final Boolean clear;
+
+    public PasteLambda(CopyLambda copyLambda, Boolean stripLeading, Boolean stripTrailing, Boolean endWithLineBreak, boolean clear) {
+        this.copyLambda = copyLambda;
+        this.stripLeading = stripLeading;
+        this.stripTrailing = stripTrailing;
+        this.endWithLineBreak = endWithLineBreak;
+        this.clear = clear;
+    }
+
+    @Override
+    public void execute(Fragment fragment, Writer writer) throws IOException {
+        String content = this.copyLambda.savedContent;
+
+        if (content == null) {
+            return;
+        }
+
+        if (this.stripTrailing){
+            content = content.stripTrailing();
+        }
+        if (this.stripLeading) {
+            content = content.stripLeading();
+        }
+        if (this.endWithLineBreak && !content.endsWith("\n")){
+            content = content + "\n";
+        }
+        writer.write(content);
+
+        if (this.clear) {
+            this.copyLambda.savedContent = null;
+        }
+    }
+}

modules/openapi-generator/src/main/resources/csharp/NullConditionalProperty.mustache

@@ -1 +1 @@
-{{#isNullable}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}{{/isNullable}}
+{{#lambda.first}}{{#isNullable}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}  {{/isNullable}}{{^required}}{{nrt?}}{{^nrt}}{{#vendorExtensions.x-is-value-type}}?{{/vendorExtensions.x-is-value-type}}{{/nrt}}  {{/required}}{{/lambda.first}}