add change, and testcase

src/expr.rs

@@ -1786,7 +1786,7 @@ pub(crate) fn wrap_struct_field(
 }
 
 pub(crate) fn struct_lit_field_separator(config: &Config) -> &str {
-    colon_spaces(config)
+    colon_spaces(config, false)
 }
 
 pub(crate) fn rewrite_field(

src/items.rs

@@ -2,6 +2,7 @@
 
 use std::borrow::Cow;
 use std::cmp::{Ordering, max, min};
+use std::backtrace::Backtrace;
 
 use regex::Regex;
 use rustc_ast::visit;
@@ -42,8 +43,8 @@ const DEFAULT_VISIBILITY: ast::Visibility = ast::Visibility {
     tokens: None,
 };
 
-fn type_annotation_separator(config: &Config) -> &str {
-    colon_spaces(config)
+fn type_annotation_separator(config: &Config, force_space_after_colon: bool) -> &str {
+    colon_spaces(config, force_space_after_colon)
 }
 
 // Statements of the form
@@ -96,7 +97,13 @@ impl Rewrite for ast::Local {
             let mut infix = String::with_capacity(32);
 
             if let Some(ref ty) = self.ty {
-                let separator = type_annotation_separator(context.config);
+
+                let force_space_after_colon = match ty.clone().into_inner().kind {
+                    ast::TyKind::Path(None, _) => true,
+                    _ => false,
+                };
+
+                let separator = type_annotation_separator(context.config, force_space_after_colon);
                 let ty_shape = if pat_str.contains('\n') {
                     shape.with_max_width(context.config)
                 } else {
@@ -1890,10 +1897,10 @@ fn rewrite_ty<R: Rewrite>(
     Ok(result)
 }
 
-fn type_annotation_spacing(config: &Config) -> (&str, &str) {
+fn type_annotation_spacing(config: &Config, force_space_after_colon: bool) -> (&str, &str) {
     (
         if config.space_before_colon() { " " } else { "" },
-        if config.space_after_colon() { " " } else { "" },
+        if force_space_after_colon || config.space_after_colon() { " " } else { "" },
     )
 }
 
@@ -1903,7 +1910,7 @@ pub(crate) fn rewrite_struct_field_prefix(
 ) -> RewriteResult {
     let vis = format_visibility(context, &field.vis);
     let safety = format_safety(field.safety);
-    let type_annotation_spacing = type_annotation_spacing(context.config);
+    let type_annotation_spacing = type_annotation_spacing(context.config, false);
     Ok(match field.ident {
         Some(name) => format!(
             "{vis}{safety}{}{}:",
@@ -1924,6 +1931,10 @@ impl Rewrite for ast::FieldDef {
     }
 }
 
+use std::sync::atomic::{AtomicUsize};
+
+static CALL_COUNT: AtomicUsize = AtomicUsize::new(0);
+
 pub(crate) fn rewrite_struct_field(
     context: &RewriteContext<'_>,
     field: &ast::FieldDef,
@@ -1939,7 +1950,11 @@ pub(crate) fn rewrite_struct_field(
         return Ok(context.snippet(field.span()).to_owned());
     }
 
-    let type_annotation_spacing = type_annotation_spacing(context.config);
+    let force_space_after_colon = match field.ty.clone().into_inner().kind {
+        ast::TyKind::Path(None, _) => true,
+        _ => false,
+    };
+    let type_annotation_spacing = type_annotation_spacing(context.config, force_space_after_colon);
     let prefix = rewrite_struct_field_prefix(context, field)?;
 
     let attrs_str = field.attrs.rewrite_result(context, shape)?;
@@ -2091,7 +2106,14 @@ fn rewrite_static(
         return None;
     }
 
-    let colon = colon_spaces(context.config);
+    // if after a semicolon is absolute path declaration (::) need to force
+    //  space after colon, because ::: syntax cannot compile
+    let force_space_after_colon = match static_parts.ty.kind {
+        ast::TyKind::Path(None, _) => true,
+        _ => false,
+    };
+    let colon = colon_spaces(context.config, force_space_after_colon);
+
     let mut prefix = format!(
         "{}{}{}{} {}{}{}",
         format_visibility(context, static_parts.vis),
@@ -2294,7 +2316,7 @@ impl Rewrite for ast::Param {
                 let (before_comment, after_comment) =
                     get_missing_param_comments(context, self.pat.span, self.ty.span, shape);
                 result.push_str(&before_comment);
-                result.push_str(colon_spaces(context.config));
+                result.push_str(colon_spaces(context.config, false));
                 result.push_str(&after_comment);
                 let overhead = last_line_width(&result);
                 let max_width = shape
@@ -2322,7 +2344,7 @@ impl Rewrite for ast::Param {
                         !has_multiple_attr_lines,
                     )?;
                     result.push_str(&before_comment);
-                    result.push_str(colon_spaces(context.config));
+                    result.push_str(colon_spaces(context.config, false));
                     result.push_str(&after_comment);
                     let overhead = last_line_width(&result);
                     let max_width = shape

src/types.rs

@@ -435,7 +435,7 @@ where
 }
 
 fn type_bound_colon(context: &RewriteContext<'_>) -> &'static str {
-    colon_spaces(context.config)
+    colon_spaces(context.config, false)
 }
 
 // If the return type is multi-lined, then force to use multiple lines for

src/utils.rs

@@ -423,9 +423,9 @@ pub(crate) fn filtered_str_fits(snippet: &str, max_width: usize, shape: Shape) -
 }
 
 #[inline]
-pub(crate) fn colon_spaces(config: &Config) -> &'static str {
+pub(crate) fn colon_spaces(config: &Config, force_space_after_colon: bool) -> &'static str {
     let before = config.space_before_colon();
-    let after = config.space_after_colon();
+    let after = force_space_after_colon || config.space_after_colon();
     match (before, after) {
         (true, true) => " : ",
         (true, false) => " :",

tests/source/issue-6470/case-1.rs

@@ -0,0 +1,15 @@
+// rustfmt-space_after_colon: false
+
+struct SomeStruct {
+    some_field: ::some_crate::Thing,
+}
+
+const THING: ::some_crate::SomeType = ::some_crate::SomeType::default();
+
+fn main() {
+    let x: ::some_crate::SomeType = ::some_crate::SomeType::default();
+    let a1: int;
+    let a2:int;
+    let a3 :int;
+    let a4 : int;
+}

tests/target/issue-6470/case-1.rs

@@ -0,0 +1,15 @@
+// rustfmt-space_after_colon: false
+
+struct SomeStruct {
+    some_field: ::some_crate::Thing,
+}
+
+const THING: ::some_crate::SomeType = ::some_crate::SomeType::default();
+
+fn main() {
+    let x: ::some_crate::SomeType = ::some_crate::SomeType::default();
+    let a1: int;
+    let a2: int;
+    let a3: int;
+    let a4: int;
+}