Rollup merge of #104012 - chenyukang:yukang/fix-103882-deli-indentation, r=petrochenkov

Improve unexpected close and mismatch delimiter hint in TokenTreesReader

Fixes #103882
Fixes #68987
Fixes #69259

The inner indentation mismatching will be covered by outer block, the new added function `report_error_prone_delim_block` will find out the error prone candidates for reporting.

20 files changed, 240 insertions, 15 deletions

diff --git a/tests/ui/parser/deli-ident-issue-1.rs b/tests/ui/parser/deli-ident-issue-1.rs
new file mode 100644
index 00000000000..54485262a0c
--- /dev/null
+++ b/tests/ui/parser/deli-ident-issue-1.rs
@@ -0,0 +1,24 @@
+#![feature(let_chains)]
+trait Demo {}
+
+impl dyn Demo {
+    pub fn report(&self) -> u32 {
+        let sum = |a: u32,
+                   b: u32,
+                   c: u32| {
+            a + b + c
+        };
+        sum(1, 2, 3)
+    }
+
+    fn check(&self, val: Option<u32>, num: Option<u32>) {
+        if let Some(b) = val
+        && let Some(c) = num {
+        && b == c {
+            //~^ ERROR expected struct
+            //~| ERROR mismatched types
+        }
+    }
+}
+
+fn main() { } //~ ERROR this file contains an unclosed delimiter
diff --git a/tests/ui/parser/deli-ident-issue-1.stderr b/tests/ui/parser/deli-ident-issue-1.stderr
new file mode 100644
index 00000000000..1119edb199f
--- /dev/null
+++ b/tests/ui/parser/deli-ident-issue-1.stderr
@@ -0,0 +1,37 @@
+error: this file contains an unclosed delimiter
+  --> $DIR/deli-ident-issue-1.rs:24:66
+   |
+LL | impl dyn Demo {
+   |               - unclosed delimiter
+...
+LL |         && let Some(c) = num {
+   |                              - this delimiter might not be properly closed...
+...
+LL |     }
+   |     - ...as it matches this but it has different indentation
+...
+LL | fn main() { }
+   |                                                                  ^
+
+error[E0574]: expected struct, variant or union type, found local variable `c`
+  --> $DIR/deli-ident-issue-1.rs:17:17
+   |
+LL |         && b == c {
+   |                 ^ not a struct, variant or union type
+
+error[E0308]: mismatched types
+  --> $DIR/deli-ident-issue-1.rs:17:9
+   |
+LL |       fn check(&self, val: Option<u32>, num: Option<u32>) {
+   |                                                           - expected `()` because of default return type
+...
+LL | /         && b == c {
+LL | |
+LL | |
+LL | |         }
+   | |_________^ expected `()`, found `bool`
+
+error: aborting due to 3 previous errors
+
+Some errors have detailed explanations: E0308, E0574.
+For more information about an error, try `rustc --explain E0308`.
diff --git a/tests/ui/parser/deli-ident-issue-2.rs b/tests/ui/parser/deli-ident-issue-2.rs
new file mode 100644
index 00000000000..5394760df70
--- /dev/null
+++ b/tests/ui/parser/deli-ident-issue-2.rs
@@ -0,0 +1,7 @@
+fn main() {
+    if 1 < 2 {
+        let _a = vec!]; //~ ERROR mismatched closing delimiter
+    }
+} //~ ERROR unexpected closing delimiter
+
+fn main() {}
diff --git a/tests/ui/parser/deli-ident-issue-2.stderr b/tests/ui/parser/deli-ident-issue-2.stderr
new file mode 100644
index 00000000000..c8f59c9d32b
--- /dev/null
+++ b/tests/ui/parser/deli-ident-issue-2.stderr
@@ -0,0 +1,19 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/deli-ident-issue-2.rs:5:1
+   |
+LL |         let _a = vec!];
+   |                      - missing open `[` for this delimiter
+LL |     }
+LL | }
+   | ^ unexpected closing delimiter
+
+error: mismatched closing delimiter: `]`
+  --> $DIR/deli-ident-issue-2.rs:2:14
+   |
+LL |     if 1 < 2 {
+   |              ^ unclosed delimiter
+LL |         let _a = vec!];
+   |                      ^ mismatched closing delimiter
+
+error: aborting due to 2 previous errors
+
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-1.rs b/tests/ui/parser/issue-68987-unmatch-issue-1.rs
new file mode 100644
index 00000000000..30e7ef46736
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-1.rs
@@ -0,0 +1,12 @@
+// This file has unexpected closing delimiter,
+
+fn func(o: Option<u32>) {
+    match o {
+        Some(_x) => {}   // Extra '}'
+            let _ = if true {};
+        }
+        None => {}
+    }
+} //~ ERROR unexpected closing delimiter
+
+fn main() {}
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-1.stderr b/tests/ui/parser/issue-68987-unmatch-issue-1.stderr
new file mode 100644
index 00000000000..2d873b46193
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-1.stderr
@@ -0,0 +1,16 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/issue-68987-unmatch-issue-1.rs:10:1
+   |
+LL |     match o {
+   |             - this delimiter might not be properly closed...
+LL |         Some(_x) => {}   // Extra '}'
+   |                     -- block is empty, you might have not meant to close it
+LL |             let _ = if true {};
+LL |         }
+   |         - ...as it matches this but it has different indentation
+...
+LL | }
+   | ^ unexpected closing delimiter
+
+error: aborting due to previous error
+
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-2.rs b/tests/ui/parser/issue-68987-unmatch-issue-2.rs
new file mode 100644
index 00000000000..89aaa68ba40
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-2.rs
@@ -0,0 +1,14 @@
+// FIXME: this case need more work to fix
+// currently the TokenTree matching ')' with '{', which is not user friendly for diagnostics
+async fn obstest() -> Result<> {
+    let obs_connect = || -> Result<(), MyError) { //~ ERROR mismatched closing delimiter
+        async {
+        }
+    }
+
+    if let Ok(version, scene_list) = obs_connect() {
+
+    } else {
+
+    }
+} //~ ERROR unexpected closing delimiter
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-2.stderr b/tests/ui/parser/issue-68987-unmatch-issue-2.stderr
new file mode 100644
index 00000000000..2c08d41a15f
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-2.stderr
@@ -0,0 +1,19 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/issue-68987-unmatch-issue-2.rs:14:1
+   |
+LL |     let obs_connect = || -> Result<(), MyError) {
+   |                                               - missing open `(` for this delimiter
+...
+LL | }
+   | ^ unexpected closing delimiter
+
+error: mismatched closing delimiter: `)`
+  --> $DIR/issue-68987-unmatch-issue-2.rs:3:32
+   |
+LL | async fn obstest() -> Result<> {
+   |                                ^ unclosed delimiter
+LL |     let obs_connect = || -> Result<(), MyError) {
+   |                                               ^ mismatched closing delimiter
+
+error: aborting due to 2 previous errors
+
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-3.rs b/tests/ui/parser/issue-68987-unmatch-issue-3.rs
new file mode 100644
index 00000000000..e98df8d7c3c
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-3.rs
@@ -0,0 +1,8 @@
+// the `{` is closed with `)`, there is a missing `(`
+fn f(i: u32, j: u32) {
+    let res = String::new();
+    let mut cnt = i;
+    while cnt < j {
+        write!&mut res, " "); //~ ERROR mismatched closing delimiter
+    }
+} //~ ERROR unexpected closing delimiter
diff --git a/tests/ui/parser/issue-68987-unmatch-issue-3.stderr b/tests/ui/parser/issue-68987-unmatch-issue-3.stderr
new file mode 100644
index 00000000000..a3fc46a1e88
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue-3.stderr
@@ -0,0 +1,19 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/issue-68987-unmatch-issue-3.rs:8:1
+   |
+LL |         write!&mut res, " ");
+   |                            - missing open `(` for this delimiter
+LL |     }
+LL | }
+   | ^ unexpected closing delimiter
+
+error: mismatched closing delimiter: `)`
+  --> $DIR/issue-68987-unmatch-issue-3.rs:5:19
+   |
+LL |     while cnt < j {
+   |                   ^ unclosed delimiter
+LL |         write!&mut res, " ");
+   |                            ^ mismatched closing delimiter
+
+error: aborting due to 2 previous errors
+
diff --git a/tests/ui/parser/issue-68987-unmatch-issue.rs b/tests/ui/parser/issue-68987-unmatch-issue.rs
new file mode 100644
index 00000000000..5a3620bf24b
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue.rs
@@ -0,0 +1,12 @@
+// This file has unexpected closing delimiter,
+
+fn func(o: Option<u32>) {
+    match o {
+        Some(_x) =>   // Missing '{'
+            let _ = if true {};
+        }
+        None => {}
+    }
+} //~ ERROR unexpected closing delimiter
+
+fn main() {}
diff --git a/tests/ui/parser/issue-68987-unmatch-issue.stderr b/tests/ui/parser/issue-68987-unmatch-issue.stderr
new file mode 100644
index 00000000000..cabd133242f
--- /dev/null
+++ b/tests/ui/parser/issue-68987-unmatch-issue.stderr
@@ -0,0 +1,16 @@
+error: unexpected closing delimiter: `}`
+  --> $DIR/issue-68987-unmatch-issue.rs:10:1
+   |
+LL |     match o {
+   |             - this delimiter might not be properly closed...
+LL |         Some(_x) =>   // Missing '{'
+LL |             let _ = if true {};
+   |                             -- block is empty, you might have not meant to close it
+LL |         }
+   |         - ...as it matches this but it has different indentation
+...
+LL | }
+   | ^ unexpected closing delimiter
+
+error: aborting due to previous error
+
diff --git a/tests/ui/parser/issue-81827.stderr b/tests/ui/parser/issue-81827.stderr
index 069de339194..867244b72e8 100644
--- a/tests/ui/parser/issue-81827.stderr
+++ b/tests/ui/parser/issue-81827.stderr
@@ -2,8 +2,9 @@ error: this file contains an unclosed delimiter
   --> $DIR/issue-81827.rs:11:27
    |
 LL | fn r()->i{0|{#[cfg(r(0{]0
-   |          -  -             ^
-   |          |  |
+   |          -  -          -  ^
+   |          |  |          |
+   |          |  |          missing open `[` for this delimiter
    |          |  unclosed delimiter
    |          unclosed delimiter
 
@@ -11,8 +12,9 @@ error: this file contains an unclosed delimiter
   --> $DIR/issue-81827.rs:11:27
    |
 LL | fn r()->i{0|{#[cfg(r(0{]0
-   |          -  -             ^
-   |          |  |
+   |          -  -          -  ^
+   |          |  |          |
+   |          |  |          missing open `[` for this delimiter
    |          |  unclosed delimiter
    |          unclosed delimiter
 
diff --git a/tests/ui/parser/issues/issue-62973.stderr b/tests/ui/parser/issues/issue-62973.stderr
index 4737bc71860..3cb6d75a675 100644
--- a/tests/ui/parser/issues/issue-62973.stderr
+++ b/tests/ui/parser/issues/issue-62973.stderr
@@ -2,8 +2,10 @@ error: this file contains an unclosed delimiter
   --> $DIR/issue-62973.rs:8:2
    |
 LL | fn p() { match s { v, E { [) {) }
-   |        -         - unclosed delimiter
-   |        |
+   |        -         -         -  - missing open `(` for this delimiter
+   |        |         |         |
+   |        |         |         missing open `(` for this delimiter
+   |        |         unclosed delimiter
    |        unclosed delimiter
 LL |
 LL |
@@ -13,8 +15,10 @@ error: this file contains an unclosed delimiter
   --> $DIR/issue-62973.rs:8:2
    |
 LL | fn p() { match s { v, E { [) {) }
-   |        -         - unclosed delimiter
-   |        |
+   |        -         -         -  - missing open `(` for this delimiter
+   |        |         |         |
+   |        |         |         missing open `(` for this delimiter
+   |        |         unclosed delimiter
    |        unclosed delimiter
 LL |
 LL |
diff --git a/tests/ui/parser/issues/issue-63116.stderr b/tests/ui/parser/issues/issue-63116.stderr
index cfdd99d1434..a1f8a77ffa7 100644
--- a/tests/ui/parser/issues/issue-63116.stderr
+++ b/tests/ui/parser/issues/issue-63116.stderr
@@ -2,8 +2,9 @@ error: this file contains an unclosed delimiter
   --> $DIR/issue-63116.rs:3:18
    |
 LL | impl W <s(f;Y(;]
-   |          -       ^
-   |          |
+   |          -     - ^
+   |          |     |
+   |          |     missing open `[` for this delimiter
    |          unclosed delimiter
 
 error: expected one of `!`, `(`, `)`, `+`, `,`, `::`, or `<`, found `;`
diff --git a/tests/ui/parser/issues/issue-69259.rs b/tests/ui/parser/issues/issue-69259.rs
new file mode 100644
index 00000000000..01fc2c08546
--- /dev/null
+++ b/tests/ui/parser/issues/issue-69259.rs
@@ -0,0 +1,3 @@
+fn main() {}
+
+fn f) {} //~ ERROR unexpected closing delimiter
diff --git a/tests/ui/parser/issues/issue-69259.stderr b/tests/ui/parser/issues/issue-69259.stderr
new file mode 100644
index 00000000000..604b7de3319
--- /dev/null
+++ b/tests/ui/parser/issues/issue-69259.stderr
@@ -0,0 +1,8 @@
+error: unexpected closing delimiter: `)`
+  --> $DIR/issue-69259.rs:3:5
+   |
+LL | fn f) {}
+   |     ^ unexpected closing delimiter
+
+error: aborting due to previous error
+
diff --git a/tests/ui/parser/issues/issue-70583-block-is-empty-1.stderr b/tests/ui/parser/issues/issue-70583-block-is-empty-1.stderr
index 39bf113ef83..46cbb056d1d 100644
--- a/tests/ui/parser/issues/issue-70583-block-is-empty-1.stderr
+++ b/tests/ui/parser/issues/issue-70583-block-is-empty-1.stderr
@@ -2,10 +2,10 @@ error: unexpected closing delimiter: `}`
   --> $DIR/issue-70583-block-is-empty-1.rs:20:1
    |
 LL | fn struct_generic(x: Vec<i32>) {
-   |                                - this opening brace...
+   |                                - this delimiter might not be properly closed...
 ...
 LL |     }
-   |     - ...matches this closing brace
+   |     - ...as it matches this but it has different indentation
 LL | }
    | ^ unexpected closing delimiter
 
diff --git a/tests/ui/parser/issues/issue-70583-block-is-empty-2.stderr b/tests/ui/parser/issues/issue-70583-block-is-empty-2.stderr
index 5d37b216427..9ae94c70186 100644
--- a/tests/ui/parser/issues/issue-70583-block-is-empty-2.stderr
+++ b/tests/ui/parser/issues/issue-70583-block-is-empty-2.stderr
@@ -1,8 +1,12 @@
 error: unexpected closing delimiter: `}`
   --> $DIR/issue-70583-block-is-empty-2.rs:14:1
    |
+LL |         match self {
+   |                    - this delimiter might not be properly closed...
 LL |             ErrorHandled::Reported => {}}
-   |                                       -- block is empty, you might have not meant to close it
+   |                                       --- ...as it matches this but it has different indentation
+   |                                       |
+   |                                       block is empty, you might have not meant to close it
 ...
 LL | }
    | ^ unexpected closing delimiter
diff --git a/tests/ui/parser/macro-mismatched-delim-paren-brace.stderr b/tests/ui/parser/macro-mismatched-delim-paren-brace.stderr
index 967a3e6fdc1..689ce1eb6b7 100644
--- a/tests/ui/parser/macro-mismatched-delim-paren-brace.stderr
+++ b/tests/ui/parser/macro-mismatched-delim-paren-brace.stderr
@@ -2,10 +2,10 @@ error: unexpected closing delimiter: `}`
   --> $DIR/macro-mismatched-delim-paren-brace.rs:5:1
    |
 LL | fn main() {
-   |           - this opening brace...
+   |           - this delimiter might not be properly closed...
 ...
 LL |     }
-   |     - ...matches this closing brace
+   |     - ...as it matches this but it has different indentation
 LL | }
    | ^ unexpected closing delimiter