raw_strings: handle format template as well

Author: samueltardieu

clippy_lints/src/raw_strings.rs

@@ -1,6 +1,6 @@
 use clippy_config::Conf;
 use clippy_utils::diagnostics::span_lint_and_then;
-use clippy_utils::source::SpanRangeExt;
+use clippy_utils::source::{SpanRangeExt, snippet_opt};
 use rustc_ast::ast::{Expr, ExprKind};
 use rustc_ast::token::LitKind;
 use rustc_errors::Applicability;
@@ -71,6 +71,23 @@ impl RawStrings {
 
 impl EarlyLintPass for RawStrings {
     fn check_expr(&mut self, cx: &EarlyContext<'_>, expr: &Expr) {
+        if let ExprKind::FormatArgs(format_args) = &expr.kind
+            && !in_external_macro(cx.sess(), format_args.span)
+            && format_args.span.check_source_text(cx, |src| src.starts_with('r'))
+            && let Some(str) = snippet_opt(cx.sess(), format_args.span)
+            && let count_hash = str.bytes().skip(1).take_while(|b| *b == b'#').count()
+            && let Some(str) = str.get(count_hash + 2..str.len() - count_hash - 1)
+        {
+            self.check_raw_string(
+                cx,
+                str,
+                format_args.span,
+                "r",
+                u8::try_from(count_hash).unwrap(),
+                "string",
+            );
+        }
+
         if let ExprKind::Lit(lit) = expr.kind
             && let (prefix, max) = match lit.kind {
                 LitKind::StrRaw(max) => ("r", max),

tests/ui/needless_raw_string.fixed

@@ -22,3 +22,12 @@ fn main() {
     b"no hashes";
     c"no hashes";
 }
+
+fn issue_13503() {
+    println!("SELECT * FROM posts");
+    println!("SELECT * FROM posts");
+    println!(r##"SELECT * FROM "posts""##);
+
+    // Test arguments as well
+    println!("{}", "foobar".len());
+}

tests/ui/needless_raw_string.rs

@@ -22,3 +22,12 @@ fn main() {
     br"no hashes";
     cr"no hashes";
 }
+
+fn issue_13503() {
+    println!(r"SELECT * FROM posts");
+    println!(r#"SELECT * FROM posts"#);
+    println!(r##"SELECT * FROM "posts""##);
+
+    // Test arguments as well
+    println!("{}", r"foobar".len());
+}

tests/ui/needless_raw_string.stderr

@@ -91,5 +91,41 @@ LL -     cr"no hashes";
 LL +     c"no hashes";
    |
 
-error: aborting due to 7 previous errors
+error: unnecessary raw string literal
+  --> tests/ui/needless_raw_string.rs:27:14
+   |
+LL |     println!(r"SELECT * FROM posts");
+   |              ^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use a plain string literal instead
+   |
+LL -     println!(r"SELECT * FROM posts");
+LL +     println!("SELECT * FROM posts");
+   |
+
+error: unnecessary raw string literal
+  --> tests/ui/needless_raw_string.rs:28:14
+   |
+LL |     println!(r#"SELECT * FROM posts"#);
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: use a plain string literal instead
+   |
+LL -     println!(r#"SELECT * FROM posts"#);
+LL +     println!("SELECT * FROM posts");
+   |
+
+error: unnecessary raw string literal
+  --> tests/ui/needless_raw_string.rs:32:20
+   |
+LL |     println!("{}", r"foobar".len());
+   |                    ^^^^^^^^^
+   |
+help: use a plain string literal instead
+   |
+LL -     println!("{}", r"foobar".len());
+LL +     println!("{}", "foobar".len());
+   |
+
+error: aborting due to 10 previous errors
 

tests/ui/needless_raw_string_hashes.fixed

@@ -24,3 +24,13 @@ fn main() {
     r"rust";
     r"hello world";
 }
+
+fn issue_13503() {
+    println!(r"SELECT * FROM posts");
+    println!(r"SELECT * FROM posts");
+    println!(r#"SELECT * FROM "posts""#);
+    println!(r#"SELECT * FROM "posts""#);
+
+    // Test arguments as well
+    println!("{}", r"foobar".len());
+}

tests/ui/needless_raw_string_hashes.rs

@@ -24,3 +24,13 @@ fn main() {
     r###"rust"###;
     r#"hello world"#;
 }
+
+fn issue_13503() {
+    println!(r"SELECT * FROM posts");
+    println!(r#"SELECT * FROM posts"#);
+    println!(r##"SELECT * FROM "posts""##);
+    println!(r##"SELECT * FROM "posts""##);
+
+    // Test arguments as well
+    println!("{}", r"foobar".len());
+}

tests/ui/needless_raw_string_hashes.stderr

@@ -187,5 +187,41 @@ LL -     r#"hello world"#;
 LL +     r"hello world";
    |
 
-error: aborting due to 15 previous errors
+error: unnecessary hashes around raw string literal
+  --> tests/ui/needless_raw_string_hashes.rs:30:14
+   |
+LL |     println!(r#"SELECT * FROM posts"#);
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove all the hashes around the string literal
+   |
+LL -     println!(r#"SELECT * FROM posts"#);
+LL +     println!(r"SELECT * FROM posts");
+   |
+
+error: unnecessary hashes around raw string literal
+  --> tests/ui/needless_raw_string_hashes.rs:31:14
+   |
+LL |     println!(r##"SELECT * FROM "posts""##);
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove one hash from both sides of the string literal
+   |
+LL -     println!(r##"SELECT * FROM "posts""##);
+LL +     println!(r#"SELECT * FROM "posts""#);
+   |
+
+error: unnecessary hashes around raw string literal
+  --> tests/ui/needless_raw_string_hashes.rs:32:14
+   |
+LL |     println!(r##"SELECT * FROM "posts""##);
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+help: remove one hash from both sides of the string literal
+   |
+LL -     println!(r##"SELECT * FROM "posts""##);
+LL +     println!(r#"SELECT * FROM "posts""#);
+   |
+
+error: aborting due to 18 previous errors