Auto merge of #46977 - est31:column_fix, r=dtolnay

 Make the output of the column! macro 1 based

Fixes  #46868.

I didn't add any regression tests as the change already had to change tests inside the codebase.

r? @dtolnay

src/libstd/macros.rs

@@ -460,9 +460,12 @@ pub mod builtin {
     /// With [`column!`] and [`file!`], these macros provide debugging information for
     /// developers about the location within the source.
     ///
-    /// The expanded expression has type `u32`, and the returned line is not
-    /// the invocation of the `line!()` macro itself, but rather the first macro
-    /// invocation leading up to the invocation of the `line!()` macro.
+    /// The expanded expression has type `u32` and is 1-based, so the first line
+    /// in each file evaluates to 1, the second to 2, etc. This is consistent
+    /// with error messages by common compilers or popular editors.
+    /// The returned line is not the invocation of the `line!` macro itself,
+    /// but rather the first macro invocation leading up to the invocation
+    /// of the `line!` macro.
     ///
     /// [`column!`]: macro.column.html
     /// [`file!`]: macro.file.html
@@ -482,9 +485,12 @@ pub mod builtin {
     /// With [`line!`] and [`file!`], these macros provide debugging information for
     /// developers about the location within the source.
     ///
-    /// The expanded expression has type `u32`, and the returned column is not
-    /// the invocation of the `column!` macro itself, but rather the first macro
-    /// invocation leading up to the invocation of the `column!` macro.
+    /// The expanded expression has type `u32` and is 1-based, so the first column
+    /// in each line evaluates to 1, the second to 2, etc. This is consistent
+    /// with error messages by common compilers or popular editors.
+    /// The returned column is not the invocation of the `column!` macro itself,
+    /// but rather the first macro invocation leading up to the invocation
+    /// of the `column!` macro.
     ///
     /// [`line!`]: macro.line.html
     /// [`file!`]: macro.file.html

src/libsyntax/ext/source_util.rs

@@ -49,7 +49,7 @@ pub fn expand_column(cx: &mut ExtCtxt, sp: Span, tts: &[tokenstream::TokenTree])
     let topmost = cx.expansion_cause().unwrap_or(sp);
     let loc = cx.codemap().lookup_char_pos(topmost.lo());
 
-    base::MacEager::expr(cx.expr_u32(topmost, loc.col.to_usize() as u32))
+    base::MacEager::expr(cx.expr_u32(topmost, loc.col.to_usize() as u32 + 1))
 }
 
 /* __rust_unstable_column!(): expands to the current column number */

src/test/run-pass/issue-26322.rs

@@ -28,9 +28,9 @@ fn main() {
         columnline!()
     } else { (0, 0) };
     let cl = columnline!();
-    assert_eq!(closure(), (8, 25));
-    assert_eq!(iflet, (8, 28));
-    assert_eq!(cl, (13, 30));
+    assert_eq!(closure(), (9, 25));
+    assert_eq!(iflet, (9, 28));
+    assert_eq!(cl, (14, 30));
     let indirect = indirectcolumnline!();
-    assert_eq!(indirect, (19, 34));
+    assert_eq!(indirect, (20, 34));
 }

src/test/run-pass/syntax-extension-source-utils.rs

@@ -22,7 +22,7 @@ macro_rules! indirect_line { () => ( line!() ) }
 
 pub fn main() {
     assert_eq!(line!(), 24);
-    assert_eq!(column!(), 15);
+    assert_eq!(column!(), 16);
     assert_eq!(indirect_line!(), 26);
     assert!((file!().ends_with("syntax-extension-source-utils.rs")));
     assert_eq!(stringify!((2*3) + 5).to_string(), "( 2 * 3 ) + 5".to_string());