1 files changed, 111 insertions, 29 deletions

diff --git a/crates/ra_ide/src/diagnostics.rs b/crates/ra_ide/src/diagnostics.rs
index fd9abb55b..05fb799d6 100644
--- a/crates/ra_ide/src/diagnostics.rs
+++ b/crates/ra_ide/src/diagnostics.rs
@@ -8,7 +8,7 @@ use std::cell::RefCell;
 
 use hir::{
     diagnostics::{AstDiagnostic, Diagnostic as _, DiagnosticSink},
-    Semantics,
+    HasSource, HirDisplay, Semantics, VariantDef,
 };
 use itertools::Itertools;
 use ra_db::SourceDatabase;
@@ -16,7 +16,7 @@ use ra_ide_db::RootDatabase;
 use ra_prof::profile;
 use ra_syntax::{
     algo,
-    ast::{self, make, AstNode},
+    ast::{self, edit::IndentLevel, make, AstNode},
     SyntaxNode, TextRange, T,
 };
 use ra_text_edit::{TextEdit, TextEditBuilder};
@@ -119,7 +119,16 @@ pub(crate) fn diagnostics(db: &RootDatabase, file_id: FileId) -> Vec<Diagnostic>
             severity: Severity::Error,
             fix: Some(fix),
         })
+    })
+    .on::<hir::diagnostics::NoSuchField, _>(|d| {
+        res.borrow_mut().push(Diagnostic {
+            range: sema.diagnostics_range(d).range,
+            message: d.message(),
+            severity: Severity::Error,
+            fix: missing_struct_field_fix(&sema, file_id, d),
+        })
     });
+
     if let Some(m) = sema.to_module_def(file_id) {
         m.diagnostics(db, &mut sink);
     };
@@ -127,6 +136,71 @@ pub(crate) fn diagnostics(db: &RootDatabase, file_id: FileId) -> Vec<Diagnostic>
     res.into_inner()
 }
 
+fn missing_struct_field_fix(
+    sema: &Semantics<RootDatabase>,
+    file_id: FileId,
+    d: &hir::diagnostics::NoSuchField,
+) -> Option<Fix> {
+    let record_expr = sema.ast(d);
+
+    let record_lit = ast::RecordLit::cast(record_expr.syntax().parent()?.parent()?)?;
+    let def_id = sema.resolve_variant(record_lit)?;
+    let module;
+    let record_fields = match VariantDef::from(def_id) {
+        VariantDef::Struct(s) => {
+            module = s.module(sema.db);
+            let source = s.source(sema.db);
+            let fields = source.value.field_def_list()?;
+            record_field_def_list(fields)?
+        }
+        VariantDef::Union(u) => {
+            module = u.module(sema.db);
+            let source = u.source(sema.db);
+            source.value.record_field_def_list()?
+        }
+        VariantDef::EnumVariant(e) => {
+            module = e.module(sema.db);
+            let source = e.source(sema.db);
+            let fields = source.value.field_def_list()?;
+            record_field_def_list(fields)?
+        }
+    };
+
+    let new_field_type = sema.type_of_expr(&record_expr.expr()?)?;
+    if new_field_type.is_unknown() {
+        return None;
+    }
+    let new_field = make::record_field_def(
+        record_expr.field_name()?,
+        make::type_ref(&new_field_type.display_source_code(sema.db, module.into()).ok()?),
+    );
+
+    let last_field = record_fields.fields().last()?;
+    let last_field_syntax = last_field.syntax();
+    let indent = IndentLevel::from_node(last_field_syntax);
+
+    let mut new_field = format!("\n{}{}", indent, new_field);
+
+    let needs_comma = !last_field_syntax.to_string().ends_with(",");
+    if needs_comma {
+        new_field = format!(",{}", new_field);
+    }
+
+    let source_change = SourceFileEdit {
+        file_id,
+        edit: TextEdit::insert(last_field_syntax.text_range().end(), new_field),
+    };
+    let fix = Fix::new("Create field", source_change.into());
+    return Some(fix);
+
+    fn record_field_def_list(field_def_list: ast::FieldDefList) -> Option<ast::RecordFieldDefList> {
+        match field_def_list {
+            ast::FieldDefList::RecordFieldDefList(it) => Some(it),
+            ast::FieldDefList::TupleFieldDefList(_) => None,
+        }
+    }
+}
+
 fn check_unnecessary_braces_in_use_statement(
     acc: &mut Vec<Diagnostic>,
     file_id: FileId,
@@ -209,7 +283,7 @@ fn check_struct_shorthand_initialization(
 mod tests {
     use insta::assert_debug_snapshot;
     use ra_syntax::SourceFile;
-    use stdx::SepBy;
+    use stdx::trim_indent;
     use test_utils::assert_eq_text;
 
     use crate::mock_analysis::{analysis_and_position, single_file};
@@ -251,6 +325,8 @@ mod tests {
     ///  * this diagnostic touches the input cursor position
     ///  * that the contents of the file containing the cursor match `after` after the diagnostic fix is applied
     fn check_apply_diagnostic_fix_from_position(fixture: &str, after: &str) {
+        let after = trim_indent(after);
+
         let (analysis, file_position) = analysis_and_position(fixture);
         let diagnostic = analysis.diagnostics(file_position.file_id).unwrap().pop().unwrap();
         let mut fix = diagnostic.fix.unwrap();
@@ -262,21 +338,6 @@ mod tests {
             actual
         };
 
-        // Strip indent and empty lines from `after`, to match the behaviour of
-        // `parse_fixture` called from `analysis_and_position`.
-        let margin = fixture
-            .lines()
-            .filter(|it| it.trim_start().starts_with("//-"))
-            .map(|it| it.len() - it.trim_start().len())
-            .next()
-            .expect("empty fixture");
-        let after = after
-            .lines()
-            .filter_map(|line| if line.len() > margin { Some(&line[margin..]) } else { None })
-            .sep_by("\n")
-            .suffix("\n")
-            .to_string();
-
         assert_eq_text!(&after, &actual);
         assert!(
             diagnostic.range.start() <= file_position.offset
@@ -287,8 +348,10 @@ mod tests {
         );
     }
 
-    fn check_apply_diagnostic_fix(before: &str, after: &str) {
-        let (analysis, file_id) = single_file(before);
+    fn check_apply_diagnostic_fix(ra_fixture_before: &str, ra_fixture_after: &str) {
+        let ra_fixture_after = &trim_indent(ra_fixture_after);
+        let (analysis, file_id) = single_file(ra_fixture_before);
+        let before = analysis.file_text(file_id).unwrap();
         let diagnostic = analysis.diagnostics(file_id).unwrap().pop().unwrap();
         let mut fix = diagnostic.fix.unwrap();
         let edit = fix.source_change.source_file_edits.pop().unwrap().edit;
@@ -297,7 +360,7 @@ mod tests {
             edit.apply(&mut actual);
             actual
         };
-        assert_eq_text!(after, &actual);
+        assert_eq_text!(ra_fixture_after, &actual);
     }
 
     /// Takes a multi-file input fixture with annotated cursor position and checks that no diagnostics
@@ -326,7 +389,6 @@ mod tests {
                 }
                 x / y<|>
             }
-
             //- /core/lib.rs
             pub mod result {
                 pub enum Result<T, E> { Ok(T), Err(E) }
@@ -357,7 +419,6 @@ mod tests {
                 }
                 <|>x
             }
-
             //- /core/lib.rs
             pub mod result {
                 pub enum Result<T, E> { Ok(T), Err(E) }
@@ -390,7 +451,6 @@ mod tests {
                 }
                 x <|>/ y
             }
-
             //- /core/lib.rs
             pub mod result {
                 pub enum Result<T, E> { Ok(T), Err(E) }
@@ -400,6 +460,7 @@ mod tests {
             use core::result::Result::{self, Ok, Err};
 
             type MyResult<T> = Result<T, ()>;
+
             fn div(x: i32, y: i32) -> MyResult<i32> {
                 if y == 0 {
                     return Err(());
@@ -512,10 +573,9 @@ mod tests {
 
             impl Expr {
                 fn new_bin(lhs: Box<Expr>, rhs: Box<Expr>) -> Expr {
-                    Expr::Bin { <|> }
+                    Expr::Bin { }
                 }
             }
-
         ";
         let after = r"
             enum Expr {
@@ -524,10 +584,9 @@ mod tests {
 
             impl Expr {
                 fn new_bin(lhs: Box<Expr>, rhs: Box<Expr>) -> Expr {
-                    Expr::Bin { lhs: (), rhs: () <|> }
+                    Expr::Bin { lhs: (), rhs: () }
                 }
             }
-
         ";
         check_apply_diagnostic_fix(before, after);
     }
@@ -650,7 +709,7 @@ mod tests {
         [
             Diagnostic {
                 message: "Missing structure fields:\n- b\n",
-                range: 224..233,
+                range: 127..136,
                 severity: Error,
                 fix: Some(
                     Fix {
@@ -791,4 +850,27 @@ fn main() {
             check_struct_shorthand_initialization,
         );
     }
+
+    #[test]
+    fn test_add_field_from_usage() {
+        check_apply_diagnostic_fix(
+            r"
+fn main() {
+    Foo { bar: 3, baz: false};
+}
+struct Foo {
+    bar: i32
+}
+",
+            r"
+fn main() {
+    Foo { bar: 3, baz: false};
+}
+struct Foo {
+    bar: i32,
+    baz: bool
+}
+",
+        )
+    }
 }