fix: remove double newlines when no variadic argument (#489)

* fix: remove double newlines when no variadic argument

* Add acceptance test

* Add changelog entry

---------

Co-authored-by: Selena Goods <[email protected]>

Author: jooola

.changes/unreleased/ENHANCEMENTS-20250613-162958.yaml

@@ -0,0 +1,5 @@
+kind: ENHANCEMENTS
+body: 'generate: Remove trailing whitespace from default function template when `.HasVariadic` evaluates to false'
+time: 2025-06-13T16:29:58.411584-04:00
+custom:
+    Issue: "489"

cmd/tfplugindocs/testdata/scripts/schema-json/generate/framework_provider_success_no_templates.txtar

@@ -9,6 +9,7 @@ cmp docs/index.md expected-index.md
 cmp docs/data-sources/example.md expected-datasource.md
 cmp docs/resources/example.md expected-resource.md
 cmp docs/functions/example.md expected-function.md
+cmp docs/functions/no-variadic.md expected-no-variadic-function.md
 cmp docs/ephemeral-resources/example.md expected-ephemeral-resource.md
 
 -- expected-output.txt --
@@ -22,6 +23,7 @@ generating missing data source content
 generating new template for data-source "scaffolding_example"
 generating missing function content
 generating new template for function "example"
+generating new template for function "no-variadic"
 generating missing ephemeral resource content
 generating new template for "scaffolding_example"
 generating missing provider content
@@ -32,6 +34,7 @@ rendering templated website to static markdown
 rendering "data-sources/example.md.tmpl"
 rendering "ephemeral-resources/example.md.tmpl"
 rendering "functions/example.md.tmpl"
+rendering "functions/no-variadic.md.tmpl"
 rendering "index.md.tmpl"
 rendering "resources/example.md.tmpl"
 -- expected-datasource.md --
@@ -99,6 +102,38 @@ example(input string, variadicInput string...) string
 1. `input` (String) Value to echo.
 <!-- variadic argument generated by tfplugindocs -->
 1. `variadicInput` (Variadic, String) Variadic input to echo.
+-- expected-no-variadic-function.md --
+---
+# generated by https://github.com/hashicorp/terraform-plugin-docs
+page_title: "no-variadic function - terraform-provider-scaffolding"
+subcategory: ""
+description: |-
+  Echo a string
+---
+
+# function: no-variadic
+
+Given a string value, returns the same value.
+
+## Example Usage
+
+```terraform
+output "test" {
+  value = provider::scaffolding::no-variadic("testvalue1")
+}
+```
+
+## Signature
+
+<!-- signature generated by tfplugindocs -->
+```text
+no-variadic(input string) string
+```
+
+## Arguments
+
+<!-- arguments generated by tfplugindocs -->
+1. `input` (String) Value to echo.
 -- expected-index.md --
 ---
 # generated by https://github.com/hashicorp/terraform-plugin-docs
@@ -207,6 +242,10 @@ data "scaffolding_example" "example" {
 output "test" {
   value = provider::scaffolding::example("testvalue1", "testvalue2")
 }
+-- examples/functions/no-variadic/function.tf --
+output "test" {
+  value = provider::scaffolding::no-variadic("testvalue1")
+}
 -- examples/provider/provider.tf --
 provider "scaffolding" {
   # example configuration here
@@ -340,6 +379,18 @@ resource "scaffolding_example" "example" {
                         "description": "Variadic input to echo.",
                         "type": "string"
                     }
+                },
+                 "no-variadic": {
+                    "description": "Given a string value, returns the same value.",
+                    "summary": "Echo a string",
+                    "return_type": "string",
+                    "parameters": [
+                        {
+                            "name": "input",
+                            "description": "Value to echo.",
+                            "type": "string"
+                        }
+                    ]
                 }
             }
         }

internal/provider/template.go

@@ -323,7 +323,7 @@ description: |-
 ## Arguments
 
 {{ .FunctionArgumentsMarkdown }}
-{{ if .HasVariadic -}}
+{{- if .HasVariadic }}
 {{ .FunctionVariadicArgumentMarkdown }}
 {{- end }}
 `