Merge pull request rust-lang#108 from jrlusby/skip_multiples

Skip suggestions with multiple options

Fixes rust-lang#78

Author: killercup

src/lib.rs

@@ -166,13 +166,13 @@ pub fn collect_suggestions<S: ::std::hash::BuildHasher>(
         .iter()
         .filter_map(|child| {
             let replacements: Vec<_> = child.spans.iter().filter_map(collect_span).collect();
-            if replacements.is_empty() {
-                None
-            } else {
+            if replacements.len() == 1 {
                 Some(Solution {
                     message: child.message.clone(),
                     replacements,
                 })
+            } else {
+                None
             }
         })
         .collect();

tests/edge-cases/skip-multi-option-lints.fixed.rs

@@ -0,0 +1,5 @@
+fn main() {
+    let xs = vec![String::from("foo")];
+    let d: &Display = &xs;
+    println!("{}", d);
+}

tests/edge-cases/skip-multi-option-lints.json

@@ -0,0 +1,100 @@
+{
+  "message": "cannot find type `Display` in this scope",
+  "code": {
+    "code": "E0412",
+    "explanation": "\nThe type name used is not in scope.\n\nErroneous code examples:\n\n```compile_fail,E0412\nimpl Something {} // error: type name `Something` is not in scope\n\n// or:\n\ntrait Foo {\n    fn bar(N); // error: type name `N` is not in scope\n}\n\n// or:\n\nfn foo(x: T) {} // type name `T` is not in scope\n```\n\nTo fix this error, please verify you didn't misspell the type name, you did\ndeclare it or imported it into the scope. Examples:\n\n```\nstruct Something;\n\nimpl Something {} // ok!\n\n// or:\n\ntrait Foo {\n    type N;\n\n    fn bar(_: Self::N); // ok!\n}\n\n// or:\n\nfn foo<T>(x: T) {} // ok!\n```\n\nAnother case that causes this error is when a type is imported into a parent\nmodule. To fix this, you can follow the suggestion and use File directly or\n`use super::File;` which will import the types from the parent namespace. An\nexample that causes this error is below:\n\n```compile_fail,E0412\nuse std::fs::File;\n\nmod foo {\n    fn some_function(f: File) {}\n}\n```\n\n```\nuse std::fs::File;\n\nmod foo {\n    // either\n    use super::File;\n    // or\n    // use std::fs::File;\n    fn foo(f: File) {}\n}\n# fn main() {} // don't insert it for us; that'll break imports\n```\n"
+  },
+  "level": "error",
+  "spans": [
+    {
+      "file_name": "./tests/everything/skip-multi-option-lints.rs",
+      "byte_start": 64,
+      "byte_end": 71,
+      "line_start": 3,
+      "line_end": 3,
+      "column_start": 13,
+      "column_end": 20,
+      "is_primary": true,
+      "text": [
+        {
+          "text": "    let d: &Display = &xs;",
+          "highlight_start": 13,
+          "highlight_end": 20
+        }
+      ],
+      "label": "not found in this scope",
+      "suggested_replacement": null,
+      "expansion": null
+    }
+  ],
+  "children": [
+    {
+      "message": "possible candidates are found in other modules, you can import them into scope",
+      "code": null,
+      "level": "help",
+      "spans": [
+        {
+          "file_name": "./tests/everything/skip-multi-option-lints.rs",
+          "byte_start": 0,
+          "byte_end": 0,
+          "line_start": 1,
+          "line_end": 1,
+          "column_start": 1,
+          "column_end": 1,
+          "is_primary": true,
+          "text": [
+            {
+              "text": "fn main() {",
+              "highlight_start": 1,
+              "highlight_end": 1
+            }
+          ],
+          "label": null,
+          "suggested_replacement": "use std::fmt::Display;\n\n",
+          "suggestion_applicability": "Unspecified",
+          "expansion": null
+        },
+        {
+          "file_name": "./tests/everything/skip-multi-option-lints.rs",
+          "byte_start": 0,
+          "byte_end": 0,
+          "line_start": 1,
+          "line_end": 1,
+          "column_start": 1,
+          "column_end": 1,
+          "is_primary": true,
+          "text": [
+            {
+              "text": "fn main() {",
+              "highlight_start": 1,
+              "highlight_end": 1
+            }
+          ],
+          "label": null,
+          "suggested_replacement": "use std::path::Display;\n\n",
+          "suggestion_applicability": "Unspecified",
+          "expansion": null
+        }
+      ],
+      "children": [],
+      "rendered": null
+    }
+  ],
+  "rendered": "error[E0412]: cannot find type `Display` in this scope\n --> ./tests/everything/skip-multi-option-lints.rs:3:13\n  |\n3 |     let d: &Display = &xs;\n  |             ^^^^^^^ not found in this scope\nhelp: possible candidates are found in other modules, you can import them into scope\n  |\n1 | use std::fmt::Display;\n  |\n1 | use std::path::Display;\n  |\n\n"
+}
+{
+  "message": "aborting due to previous error",
+  "code": null,
+  "level": "error",
+  "spans": [],
+  "children": [],
+  "rendered": "error: aborting due to previous error\n\n"
+}
+{
+  "message": "For more information about this error, try `rustc --explain E0412`.",
+  "code": null,
+  "level": "",
+  "spans": [],
+  "children": [],
+  "rendered": "For more information about this error, try `rustc --explain E0412`.\n"
+}

tests/edge-cases/skip-multi-option-lints.rs

@@ -0,0 +1,5 @@
+fn main() {
+    let xs = vec![String::from("foo")];
+    let d: &Display = &xs;
+    println!("{}", d);
+}

tests/edge_cases.rs

@@ -0,0 +1,10 @@
+extern crate rustfix;
+use std::collections::HashSet;
+use std::fs;
+
+#[test]
+fn multiple_fix_options_yield_no_suggestions() {
+    let json = fs::read_to_string("./tests/edge-cases/skip-multi-option-lints.json").unwrap();
+    let expected_suggestions = rustfix::get_suggestions_from_json(&json, &HashSet::new()).unwrap();
+    assert!(expected_suggestions.is_empty());
+}