1 files changed, 99 insertions, 0 deletions
diff --git a/tests/ui/fmt/ifmt-bad-arg.rs b/tests/ui/fmt/ifmt-bad-arg.rs
new file mode 100644
index 00000000000..68861d7bf3f
--- /dev/null
+++ b/tests/ui/fmt/ifmt-bad-arg.rs
@@ -0,0 +1,99 @@
+fn main() {
+    // bad arguments to the format! call
+
+    // bad number of arguments, see #44954 (originally #15780)
+
+    format!("{}");
+    //~^ ERROR: 1 positional argument in format string, but no arguments were given
+
+    format!("{1}", 1);
+    //~^ ERROR: invalid reference to positional argument 1 (there is 1 argument)
+    //~^^ ERROR: argument never used
+
+    format!("{} {}");
+    //~^ ERROR: 2 positional arguments in format string, but no arguments were given
+
+    format!("{0} {1}", 1);
+    //~^ ERROR: invalid reference to positional argument 1 (there is 1 argument)
+
+    format!("{0} {1} {2}", 1, 2);
+    //~^ ERROR: invalid reference to positional argument 2 (there are 2 arguments)
+
+    format!("{} {value} {} {}", 1, value=2);
+    //~^ ERROR: 3 positional arguments in format string, but there are 2 arguments
+    format!("{name} {value} {} {} {} {} {} {}", 0, name=1, value=2);
+    //~^ ERROR: 6 positional arguments in format string, but there are 3 arguments
+
+    format!("{} {foo} {} {bar} {}", 1, 2, 3);
+    //~^ ERROR: cannot find value `foo` in this scope
+    //~^^ ERROR: cannot find value `bar` in this scope
+
+    format!("{foo}");                //~ ERROR: cannot find value `foo` in this scope
+    format!("", 1, 2);               //~ ERROR: multiple unused formatting arguments
+    format!("{}", 1, 2);             //~ ERROR: argument never used
+    format!("{1}", 1, 2);            //~ ERROR: argument never used
+    format!("{}", 1, foo=2);         //~ ERROR: named argument never used
+    format!("{foo}", 1, foo=2);      //~ ERROR: argument never used
+    format!("", foo=2);              //~ ERROR: named argument never used
+    format!("{} {}", 1, 2, foo=1, bar=2);  //~ ERROR: multiple unused formatting arguments
+
+    format!("{foo}", foo=1, foo=2);  //~ ERROR: duplicate argument
+    format!("{foo} {} {}", foo=1, 2);   //~ ERROR: positional arguments cannot follow
+
+    // bad named arguments, #35082
+
+    format!("{valuea} {valueb}", valuea=5, valuec=7);
+    //~^ ERROR cannot find value `valueb` in this scope
+    //~^^ ERROR named argument never used
+
+    // bad syntax of the format string
+
+    format!("{"); //~ ERROR: expected `'}'` but string was terminated
+
+    format!("foo } bar"); //~ ERROR: unmatched `}` found
+    format!("foo }"); //~ ERROR: unmatched `}` found
+
+    format!("foo %s baz", "bar"); //~ ERROR: argument never used
+
+    format!(r##"
+
+        {foo}
+
+    "##);
+    //~^^^ ERROR: cannot find value `foo` in this scope
+
+    // bad syntax in format string with multiple newlines, #53836
+    format!("first number: {}
+second number: {}
+third number: {}
+fourth number: {}
+fifth number: {}
+sixth number: {}
+seventh number: {}
+eighth number: {}
+ninth number: {
+tenth number: {}",
+        1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
+    //~^^ ERROR: invalid format string
+    println!("{} {:.*} {}", 1, 3.2, 4);
+    //~^ ERROR 4 positional arguments in format string, but there are 3 arguments
+    //~| ERROR mismatched types
+    println!("{} {:07$.*} {}", 1, 3.2, 4);
+    //~^ ERROR invalid reference to positional arguments 3 and 7 (there are 3 arguments)
+    //~| ERROR mismatched types
+    println!("{} {:07$} {}", 1, 3.2, 4);
+    //~^ ERROR invalid reference to positional argument 7 (there are 3 arguments)
+    println!("{:foo}", 1); //~ ERROR unknown format trait `foo`
+    println!("{5} {:4$} {6:7$}", 1);
+    //~^ ERROR invalid reference to positional arguments 4, 5, 6 and 7 (there is 1 argument)
+    let foo = 1;
+    println!("{foo:0$}");
+    //~^ ERROR invalid reference to positional argument 0 (no arguments were given)
+
+    // We used to ICE here because we tried to unconditionally access the first argument, which
+    // doesn't exist.
+    println!("{:.*}");
+    //~^ ERROR 2 positional arguments in format string, but no arguments were given
+    println!("{:.0$}");
+    //~^ ERROR invalid reference to positional argument 0 (no arguments were given)
+}