Allow to disable trailing commas

doku-derive/src/expand/expand_field.rs

@@ -105,12 +105,10 @@ impl Field {
             self.example = quote! {
                 Some(::doku::Example::Literal(#literal_example))
             };
-        } else {
-            if !examples.is_empty() {
-                self.example = quote! {
-                    Some(::doku::Example::from(&[#(#examples,)*][..]))
-                };
-            }
+        } else if !examples.is_empty() {
+            self.example = quote! {
+                Some(::doku::Example::from(&[#(#examples,)*][..]))
+            };
         }
 
         if !metas.is_empty() {

doku-derive/src/expand/expand_fields.rs

@@ -4,7 +4,7 @@ pub fn expand_fields(fields: &syn::Fields) -> Result<TokenStream2> {
     match fields {
         syn::Fields::Named(inner) => expand_named_fields(inner),
         syn::Fields::Unnamed(inner) => expand_unnamed_fields(inner),
-        syn::Fields::Unit => expand_unit_fields(),
+        syn::Fields::Unit => Ok(expand_unit_fields()),
     }
 }
 
@@ -36,8 +36,8 @@ fn expand_unnamed_fields(fields: &syn::FieldsUnnamed) -> Result<TokenStream2> {
     })
 }
 
-fn expand_unit_fields() -> Result<TokenStream2> {
-    Ok(quote! {
+fn expand_unit_fields() -> TokenStream2 {
+    quote! {
         ::doku::Fields::Unit
-    })
+    }
 }

doku/src/printers/json/formatting/objects_style.rs

@@ -15,7 +15,7 @@ pub struct ObjectsStyle {
     /// }
     ///
     /// let fmt_no_quotes = doku::json::Formatting {
-    ///     objects_style: doku::json::ObjectsStyle { surround_keys_with_quotes: false },
+    ///     objects_style: doku::json::ObjectsStyle { surround_keys_with_quotes: false, ..Default::default() },
     ///     ..Default::default()
     /// };
     ///
@@ -28,7 +28,7 @@ pub struct ObjectsStyle {
     /// "#, doc);
     ///
     /// let fmt_quotes = doku::json::Formatting {
-    ///     objects_style: doku::json::ObjectsStyle { surround_keys_with_quotes: true },
+    ///     objects_style: doku::json::ObjectsStyle { surround_keys_with_quotes: true, ..Default::default() },
     ///     ..Default::default()
     /// };
     ///
@@ -41,12 +41,54 @@ pub struct ObjectsStyle {
     /// "#, doc);
     /// ```
     pub surround_keys_with_quotes: bool,
+
+    /// Whether to use comma to separate properties
+    ///
+    /// ```
+    /// use doku::Document;
+    ///
+    /// #[derive(Document)]
+    /// struct Person {
+    ///     name: String,
+    ///     address: String,
+    /// }
+    ///
+    /// let fmt_no_quotes = doku::json::Formatting {
+    ///     objects_style: doku::json::ObjectsStyle { use_comma_as_separator: false, ..Default::default() },
+    ///     ..Default::default()
+    /// };
+    ///
+    /// let doc = doku::to_json_fmt::<Person>(&fmt_no_quotes);
+    ///
+    /// doku::assert_doc!(r#"
+    ///   {
+    ///     "name": "string"
+    ///     "address": "string"
+    ///   }
+    /// "#, doc);
+    ///
+    /// let fmt_quotes = doku::json::Formatting {
+    ///     objects_style: doku::json::ObjectsStyle { use_comma_as_separator: true, ..Default::default() },
+    ///     ..Default::default()
+    /// };
+    ///
+    /// let doc = doku::to_json_fmt::<Person>(&fmt_quotes);
+    ///
+    /// doku::assert_doc!(r#"
+    ///   {
+    ///     "name": "string",
+    ///     "address": "string"
+    ///   }
+    /// "#, doc);
+    /// ```
+    pub use_comma_as_separator: bool,
 }
 
 impl Default for ObjectsStyle {
     fn default() -> Self {
         Self {
             surround_keys_with_quotes: true,
+            use_comma_as_separator: true,
         }
     }
 }

doku/src/printers/json/output.rs

@@ -46,8 +46,15 @@ impl Output {
         } else {
             self.write(key);
         }
-        self.write(':');
-        self.write(' ');
+        self.write_char(':');
+        self.write_char(' ');
+    }
+
+    pub fn write_property_separator_ln(&mut self) {
+        if self.fmt.objects_style.use_comma_as_separator {
+            self.write_char(',');
+        }
+        self.ln();
     }
 
     pub fn write(&mut self, str: impl ToString) {

doku/src/printers/json/print_array/sketch.rs

@@ -18,7 +18,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
                     .with_example(Some(*example))
                     .print();
 
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
 
                 // TODO if `size.is_some()` and this is the last example, the comma should not be printed
             }
@@ -28,7 +28,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
             }
         } else {
             self.nested().with_ty(ty).print();
-            self.out.writeln(",");
+            self.out.write_property_separator_ln();
             self.out.writeln("/* ... */");
         }
 

doku/src/printers/json/print_array/sketch/expand_variants/for_adjacently_tagged_enum.rs

@@ -26,7 +26,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
 
         for (variant_idx, variant) in variants {
             if variant_idx > 0 {
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
             }
 
             let comment = variant.comment.or_else(|| {
@@ -50,7 +50,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
             if let Fields::Named { .. } | Fields::Unnamed { .. } =
                 variant.fields
             {
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
                 self.out.write_key_and_separator(content);
                 self.print_fields(&variant.fields, None);
             }

doku/src/printers/json/print_array/sketch/expand_variants/for_externally_tagged_enum.rs

@@ -26,7 +26,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
 
         for (variant_idx, variant) in variants {
             if variant_idx > 0 {
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
             }
 
             let comment = variant.comment.or_else(|| {

doku/src/printers/json/print_array/sketch/expand_variants/for_untagged_enum.rs

@@ -81,7 +81,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
 
         for (variant_idx, variant) in variants.iter().enumerate() {
             if variant_idx > 0 {
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
             }
 
             self.print_fields(fields_obj, Some(variant));

doku/src/printers/json/print_enum/commented/comment.rs

@@ -72,6 +72,11 @@ fn render_variant(
     tag: Tag,
     variant: &Variant,
 ) -> String {
+    let comma = if ctxt.fmt.objects_style.use_comma_as_separator {
+        ","
+    } else {
+        ""
+    };
     let quote = if ctxt.fmt.objects_style.surround_keys_with_quotes {
         "\""
     } else {
@@ -90,11 +95,12 @@ fn render_variant(
             }
 
             fields => format!(
-                "{{\n\t{q}{}{q}: \"{}\",\n\t{q}{}{q}: {}\n}}",
+                "{{\n\t{q}{}{q}: \"{}\"{c}\n\t{q}{}{q}: {}\n}}",
                 tag,
                 variant.id,
                 content,
                 render_variant_fields(ctxt, fields, false, true),
+                c = comma,
                 q = quote
             ),
         },
@@ -110,7 +116,7 @@ fn render_variant(
                     )
                 } else {
                     format!(
-                        "{{\n\t{q}{}{q}: \"{}\",\n\t{}\n}}",
+                        "{{\n\t{q}{}{q}: \"{}\"{c}\n\t{}\n}}",
                         tag,
                         variant.id,
                         render_variant_fields(
@@ -119,6 +125,7 @@ fn render_variant(
                             true,
                             true,
                         ),
+                        c = comma,
                         q = quote
                     )
                 }

doku/src/printers/json/print_enum/separated/multiline.rs

@@ -41,17 +41,17 @@ fn print_variant<'ty>(
             ctxt.out.writeln("{");
             ctxt.out.inc_indent();
             ctxt.out.write_key_and_separator(tag);
-            ctxt.out.write(format!(r#""{}","#, variant.id));
+            ctxt.out.write(format!(r#""{}""#, variant.id));
+            ctxt.out.write_property_separator_ln();
 
             if let Fields::Named { .. } | Fields::Unnamed { .. } =
                 variant.fields
             {
-                ctxt.out.ln();
                 ctxt.out.write_key_and_separator(content);
                 ctxt.print_fields(&variant.fields, None);
+                ctxt.out.ln();
             }
 
-            ctxt.out.ln();
             ctxt.out.dec_indent();
             ctxt.out.write("}");
         }
@@ -60,7 +60,8 @@ fn print_variant<'ty>(
             ctxt.out.writeln("{");
             ctxt.out.inc_indent();
             ctxt.out.write_key_and_separator(tag);
-            ctxt.out.writeln(format!(r#""{}","#, variant.id));
+            ctxt.out.write(format!(r#""{}""#, variant.id));
+            ctxt.out.write_property_separator_ln();
 
             if let Fields::Named { .. } | Fields::Unnamed { .. } =
                 variant.fields

doku/src/printers/json/print_fields/named.rs

@@ -43,7 +43,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
         variant: Option<&'ty Variant>,
     ) {
         if field_id > 0 {
-            self.out.writeln(",");
+            self.out.write_property_separator_ln();
         }
 
         let field_val = self
@@ -57,7 +57,8 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
             );
 
             self.out.write_key_and_separator(tag);
-            self.out.writeln(format!(r#""{}","#, variant.id));
+            self.out.write(format!(r#""{}""#, variant.id));
+            self.out.write_property_separator_ln();
             self.out.write_key_and_separator(field_name);
             self.print_fields(&variant.fields, None);
 

doku/src/printers/json/print_map.rs

@@ -13,7 +13,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
             self.nested().with_ty(key).set_is_key().print();
             self.out.write(": ");
             self.nested().with_ty(value).print();
-            self.out.writeln(",");
+            self.out.write_property_separator_ln();
             self.out.write("/* ... */");
         }
 

doku/src/printers/json/print_tuple.rs

@@ -19,7 +19,7 @@ impl<'ty> Ctxt<'_, 'ty, '_> {
 
         for (field_id, field) in fields.iter().enumerate() {
             if field_id > 0 {
-                self.out.writeln(",");
+                self.out.write_property_separator_ln();
             }
 
             self.nested().with_ty(&field).print();

doku/tests/printers.rs

@@ -80,6 +80,18 @@ mod prelude {
             doku::to_json::<$ty>()
         }};
 
+        (@assert to_json_without_comma($ty:ty)) => {{
+            printer_test!(@assert to_json_without_comma($ty, {}))
+        }};
+
+        (@assert to_json_without_comma($ty:ty, $fmt:tt)) => {{
+            let fmt = serde_json::json!($fmt);
+            let mut fmt: doku::json::Formatting = serde_json::from_value(fmt).expect("Given formatting is not valid");
+            fmt.objects_style.use_comma_as_separator = false;
+
+            doku::to_json_fmt::<$ty>(&fmt)
+        }};
+
         (@assert to_json_without_key_quotes($ty:ty)) => {{
             printer_test!(@assert to_json_without_key_quotes($ty, {}))
         }};
@@ -110,6 +122,13 @@ mod prelude {
             doku::to_json_val(&<$ty>::default())
         }};
 
+        (@assert to_json_val_without_comma($ty:ty)) => {{
+            let mut fmt = doku::json::Formatting::default();
+            fmt.objects_style.use_comma_as_separator = false;
+
+            doku::to_json_fmt_val(&fmt, &<$ty>::default())
+        }};
+
         (@assert to_json_val_without_key_quotes($ty:ty)) => {{
             let mut fmt = doku::json::Formatting::default();
             fmt.objects_style.surround_keys_with_quotes = false;

doku/tests/printers/enum/nested/mod.rs

@@ -28,11 +28,11 @@ printer_test! {
          "enums_style": "Separated",
     }),
 
-    "output.without-key-quotes.commented.json" => to_json_without_key_quotes(Ty, {
+   "output.without-key-quotes.commented.json" => to_json_without_key_quotes(Ty, {
         "enums_style": "Commented",
-   }),
+    }),
 
-   "output.without-key-quotes.separated.json" => to_json_without_key_quotes(Ty, {
+    "output.without-key-quotes.separated.json" => to_json_without_key_quotes(Ty, {
         "enums_style": "Separated",
-   }),
+    }),
 }

doku/tests/printers/enum/of_tag/adjacent/of_fields/named/mod.rs

@@ -75,6 +75,14 @@ printer_test! {
          "enums_style": "Separated",
     }),
 
+    "output.without-comma.with-user-comments-wrapped.commented.json" => to_json_without_comma(WithUserCommentsWrapped, {
+          "enums_style": "Commented",
+     }),
+
+     "output.without-comma.with-user-comments-wrapped.separated.json" => to_json_without_comma(WithUserCommentsWrapped, {
+          "enums_style": "Separated",
+     }),
+
     "output.without-key-quotes.with-user-comments-wrapped.commented.json" => to_json_without_key_quotes(WithUserCommentsWrapped, {
           "enums_style": "Commented",
      }),

doku/tests/printers/enum/of_tag/adjacent/of_fields/named/output.without-comma.with-user-comments-wrapped.commented.json

@@ -0,0 +1,22 @@
+{
+  // Possible variants:
+  // - {
+  //     "t": "Foo"
+  //     "c": {
+  //       // Some comment
+  //       "a": "string"
+  //     }
+  //   }
+  //   = This is `Foo`
+  // - {
+  //     "t": "Bar"
+  //     "c": {
+  //       // Some comment
+  //       "a": "string"
+  //       // Some comment
+  //       "b": 123
+  //     }
+  //   }
+  //   = This is `Bar`
+  "value": { "t": "Foo", "c": ... }
+}