Add convenience functions to SourceChange for creating single edits

crates/ra_ide_api/src/assists.rs

@@ -17,14 +17,9 @@ pub(crate) fn assists(db: &RootDatabase, frange: FileRange) -> Vec<Assist> {
             let file_id = frange.file_id;
             let file_edit = SourceFileEdit { file_id, edit: action.edit };
             let id = label.id;
-            let change = SourceChange {
+            let change = SourceChange::source_edit(label.label, file_edit).with_cursor_opt(
-                label: label.label,
+                action.cursor_position.map(|offset| FilePosition { offset, file_id }),
-                source_file_edits: vec![file_edit],
+            );
-                file_system_edits: vec![],
-                cursor_position: action
-                    .cursor_position
-                    .map(|offset| FilePosition { offset, file_id }),
-            };
             Assist { id, change }
         })
         .collect()

crates/ra_ide_api/src/diagnostics.rs

@@ -71,12 +71,10 @@ fn check_unnecessary_braces_in_use_statement(
             range,
             message: format!("Unnecessary braces in use statement"),
             severity: Severity::WeakWarning,
-            fix: Some(SourceChange {
+            fix: Some(SourceChange::source_edit(
-                label: "Remove unnecessary braces".to_string(),
+                "Remove unnecessary braces",
-                source_file_edits: vec![SourceFileEdit { file_id, edit }],
+                SourceFileEdit { file_id, edit },
-                file_system_edits: Vec::new(),
+            )),
-                cursor_position: None,
-            }),
         });
     }
 
@@ -119,12 +117,10 @@ fn check_struct_shorthand_initialization(
                     range: named_field.syntax().range(),
                     message: format!("Shorthand struct initialization"),
                     severity: Severity::WeakWarning,
-                    fix: Some(SourceChange {
+                    fix: Some(SourceChange::source_edit(
-                        label: "use struct shorthand initialization".to_string(),
+                        "use struct shorthand initialization",
-                        source_file_edits: vec![SourceFileEdit { file_id, edit }],
+                        SourceFileEdit { file_id, edit },
-                        file_system_edits: Vec::new(),
+                    )),
-                        cursor_position: None,
-                    }),
                 });
             }
         }
@@ -144,12 +140,7 @@ fn check_module(
             Problem::UnresolvedModule { candidate } => {
                 let create_file =
                     FileSystemEdit::CreateFile { source_root, path: candidate.clone() };
-                let fix = SourceChange {
+                let fix = SourceChange::system_edit("create module", create_file);
-                    label: "create module".to_string(),
-                    source_file_edits: Vec::new(),
-                    file_system_edits: vec![create_file],
-                    cursor_position: None,
-                };
                 Diagnostic {
                     range: name_node.range(),
                     message: "unresolved module".to_string(),

crates/ra_ide_api/src/lib.rs

@@ -97,6 +97,44 @@ pub struct SourceChange {
     pub cursor_position: Option<FilePosition>,
 }
 
+impl SourceChange {
+    pub fn source_edits<L: Into<String>>(label: L, edits: Vec<SourceFileEdit>) -> Self {
+        SourceChange {
+            label: label.into(),
+            source_file_edits: edits,
+            file_system_edits: vec![],
+            cursor_position: None,
+        }
+    }
+
+    pub fn system_edits<L: Into<String>>(label: L, edits: Vec<FileSystemEdit>) -> Self {
+        SourceChange {
+            label: label.into(),
+            source_file_edits: vec![],
+            file_system_edits: edits,
+            cursor_position: None,
+        }
+    }
+
+    pub fn source_edit<L: Into<String>>(label: L, edit: SourceFileEdit) -> Self {
+        SourceChange::source_edits(label, vec![edit])
+    }
+
+    pub fn system_edit<L: Into<String>>(label: L, edit: FileSystemEdit) -> Self {
+        SourceChange::system_edits(label, vec![edit])
+    }
+
+    pub fn with_cursor(mut self, cursor_position: FilePosition) -> Self {
+        self.cursor_position = Some(cursor_position);
+        self
+    }
+
+    pub fn with_cursor_opt(mut self, cursor_position: Option<FilePosition>) -> Self {
+        self.cursor_position = cursor_position;
+        self
+    }
+}
+
 #[derive(Debug)]
 pub struct SourceFileEdit {
     pub file_id: FileId,
@@ -285,12 +323,7 @@ impl Analysis {
             file_id: frange.file_id,
             edit: join_lines::join_lines(&file, frange.range),
         };
-        SourceChange {
+        SourceChange::source_edit("join lines", file_edit)
-            label: "join lines".to_string(),
-            source_file_edits: vec![file_edit],
-            file_system_edits: vec![],
-            cursor_position: None,
-        }
     }
 
     /// Returns an edit which should be applied when opening a new line, fixing
@@ -305,12 +338,10 @@ impl Analysis {
     pub fn on_eq_typed(&self, position: FilePosition) -> Option<SourceChange> {
         let file = self.db.parse(position.file_id);
         let edit = typing::on_eq_typed(&file, position.offset)?;
-        Some(SourceChange {
+        Some(SourceChange::source_edit(
-            label: "add semicolon".to_string(),
+            "add semicolon",
-            source_file_edits: vec![SourceFileEdit { edit, file_id: position.file_id }],
+            SourceFileEdit { edit, file_id: position.file_id },
-            file_system_edits: vec![],
+        ))
-            cursor_position: None,
-        })
     }
 
     /// Returns an edit which should be applied when a dot ('.') is typed on a blank line, indenting the line appropriately.

crates/ra_ide_api/src/typing.rs

@@ -31,12 +31,14 @@ pub(crate) fn on_enter(db: &RootDatabase, position: FilePosition) -> Option<Sour
     let cursor_position = position.offset + TextUnit::of_str(&inserted);
     let mut edit = TextEditBuilder::default();
     edit.insert(position.offset, inserted);
-    Some(SourceChange {
+
-        label: "on enter".to_string(),
+    Some(
-        source_file_edits: vec![SourceFileEdit { edit: edit.finish(), file_id: position.file_id }],
+        SourceChange::source_edit(
-        file_system_edits: vec![],
+            "on enter",
-        cursor_position: Some(FilePosition { offset: cursor_position, file_id: position.file_id }),
+            SourceFileEdit { edit: edit.finish(), file_id: position.file_id },
-    })
+        )
+        .with_cursor(FilePosition { offset: cursor_position, file_id: position.file_id }),
+    )
 }
 
 fn node_indent<'a>(file: &'a SourceFile, node: &SyntaxNode) -> Option<&'a str> {