Add more stack macro tests

nalgebra-macros/src/lib.rs

@@ -24,7 +24,7 @@ use syn::spanned::Spanned;
 use syn::{parse_macro_input, Token};
 use syn::{Expr, Lit};
 
-use proc_macro2::{Delimiter, Spacing, TokenStream as TokenStream2, TokenTree};
+use proc_macro2::{Delimiter, Span, Spacing, TokenStream as TokenStream2, TokenTree};
 use proc_macro2::{Group, Punct};
 
 struct Matrix {
@@ -445,11 +445,14 @@ impl ConcatElem {
 #[proc_macro]
 pub fn stack(stream: TokenStream) -> TokenStream {
     let matrix = parse_macro_input!(stream as Matrix);
-    proc_macro::TokenStream::from(stack_impl("__11f075cdd4a86538", matrix))
+    proc_macro::TokenStream::from(match stack_impl("__11f075cdd4a86538", matrix) {
+        Ok(res) => res,
+        Err(err) => err.into_compile_error(),
+    })
 }
 
 #[allow(clippy::too_many_lines)]
-fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
+fn stack_impl(prefix: &str, matrix: Matrix) -> Result<TokenStream2> {
     let n_macro_rows = matrix.nrows();
     let n_macro_cols = matrix.ncols();
 
@@ -485,7 +488,7 @@ fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
         }).reduce(|a, b| quote!{
             <nalgebra::constraint::ShapeConstraint as nalgebra::constraint::DimEq<_, _>>::representative(#a, #b)
                 .expect("The concatenated matrices do not have the same number of columns")
-        }).expect("At least one element in each row must be an expression of type `Matrix`");
+        }).ok_or(Error::new(Span::call_site(), "At least one element in each row must be an expression of type `Matrix`"))?;
 
         let size_ident = format_ident!("{}_cat_row_{}_size", prefix, i);
         let offset_ident = format_ident!("{}_cat_row_{}_offset", prefix, i);
@@ -511,7 +514,7 @@ fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
         }).reduce(|a, b| quote!{
             <nalgebra::constraint::ShapeConstraint as nalgebra::constraint::DimEq<_, _>>::representative(#a, #b)
                 .expect("The concatenated matrices do not have the same number of rows")
-        }).expect("At least one element in each column must be an expression of type `Matrix`");
+        }).ok_or(Error::new(Span::call_site(), "At least one element in each column must be an expression of type `Matrix`"))?;
 
         let size_ident = format_ident!("{}_cat_col_{}_size", prefix, j);
         let offset_ident = format_ident!("{}_cat_col_{}_offset", prefix, j);
@@ -540,7 +543,7 @@ fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
                 <_ as nalgebra::DimAdd<_>>::add(#a, #b)
             }
         })
-        .expect("More than zero rows in concatenation");
+        .ok_or(Error::new(Span::call_site(), "`stack` macro cannot be used without any arguments"))?;
 
     let num_cols = (0..n_macro_cols)
         .map(|j| {
@@ -552,7 +555,7 @@ fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
                 <_ as nalgebra::DimAdd<_>>::add(#a, #b)
             }
         })
-        .unwrap();
+        .ok_or(Error::new(Span::call_site(), "`stack` macro cannot be used without any arguments"))?;
 
     // It should be possible to use `uninitialized_generic` here instead
     // however that would mean that the macro needs to generate unsafe code
@@ -583,12 +586,12 @@ fn stack_impl(prefix: &str, matrix: Matrix) -> TokenStream2 {
         }
     }
 
-    quote! {
+    Ok(quote! {
         {
             #output
             matrix
         }
-    }
+    })
 }
 
 #[cfg(test)]
@@ -602,7 +605,7 @@ mod tests {
             0, b;
         ];
 
-        let result = stack_impl("", input);
+        let result = stack_impl("", input).unwrap();
 
         let expected = quote! {{
             let _cat_0_0 = a;
@@ -645,7 +648,7 @@ mod tests {
             e, 0, 0;
         ];
 
-        let result = stack_impl("", input);
+        let result = stack_impl("", input).unwrap();
 
         let expected = quote! {{
             let _cat_0_0 = a;

nalgebra-macros/tests/tests.rs

@@ -365,3 +365,65 @@ fn stack_nested() {
 
     assert_eq_and_type!(m, res);
 }
+
+#[test]
+fn stack_single() {
+    let a = matrix![1, 2; 3, 4];
+    let b = stack![a];
+
+    assert_eq_and_type!(a, b);
+}
+
+#[test]
+fn stack_single_row() {
+    let a = matrix![1, 2; 3, 4];
+    let m = stack![a, a];
+
+    let res = matrix![
+        1, 2, 1, 2;
+        3, 4, 3, 4;
+    ];
+
+    assert_eq_and_type!(m, res);
+}
+
+#[test]
+fn stack_single_col() {
+    let a = matrix![1, 2; 3, 4];
+    let m = stack![a; a];
+
+    let res = matrix![
+        1, 2;
+        3, 4;
+        1, 2;
+        3, 4;
+    ];
+
+    assert_eq_and_type!(m, res);
+}
+
+#[test]
+fn stack_expr() {
+    let a = matrix![1, 2; 3, 4];
+    let b = matrix![5, 6; 7, 8];
+    let m = stack![a + b; b - a];
+
+    let res = matrix![
+        6, 8;
+        10, 12;
+        4, 4;
+        4, 4;
+    ];
+
+    assert_eq_and_type!(m, res);
+}
+
+#[test]
+fn stack_trybuild_tests() {
+    let t = trybuild::TestCases::new();
+
+    // Verify error message when try to conactenate no matrices
+    t.compile_fail("tests/trybuild/stack_empty.rs");
+    t.compile_fail("tests/trybuild/stack_empty_row.rs");
+    t.compile_fail("tests/trybuild/stack_empty_col.rs");
+}

nalgebra-macros/tests/trybuild/stack_empty.rs

@@ -0,0 +1,5 @@
+use nalgebra_macros::stack;
+
+fn main() {
+    stack![];
+}

nalgebra-macros/tests/trybuild/stack_empty.stderr

@@ -0,0 +1,7 @@
+error: `stack` macro cannot be used without any arguments
+ --> tests/trybuild/stack_empty.rs:4:5
+  |
+4 |     stack![];
+  |     ^^^^^^^^
+  |
+  = note: this error originates in the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)

nalgebra-macros/tests/trybuild/stack_empty_col.rs

@@ -0,0 +1,6 @@
+use nalgebra_macros::{matrix, stack};
+
+fn main() {
+    let m = matrix![1, 2; 3, 4];
+    stack![0, m];
+}

nalgebra-macros/tests/trybuild/stack_empty_col.stderr

@@ -0,0 +1,7 @@
+error: At least one element in each column must be an expression of type `Matrix`
+ --> tests/trybuild/stack_empty_col.rs:5:5
+  |
+5 |     stack![0, m];
+  |     ^^^^^^^^^^^^
+  |
+  = note: this error originates in the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)

nalgebra-macros/tests/trybuild/stack_empty_row.rs

@@ -0,0 +1,6 @@
+use nalgebra_macros::{matrix, stack};
+
+fn main() {
+    let m = matrix![1, 2; 3, 4];
+    stack![0; m];
+}

nalgebra-macros/tests/trybuild/stack_empty_row.stderr

@@ -0,0 +1,7 @@
+error: At least one element in each row must be an expression of type `Matrix`
+ --> tests/trybuild/stack_empty_row.rs:5:5
+  |
+5 |     stack![0; m];
+  |     ^^^^^^^^^^^^
+  |
+  = note: this error originates in the macro `stack` (in Nightly builds, run with -Z macro-backtrace for more info)