18 files changed, 143 insertions, 0 deletions
diff --git a/progs/tests/func/calls_inside_calls.sy b/progs/tests/func/calls_inside_calls.sy
new file mode 100644
index 0000000..5f6716b
--- /dev/null
+++ b/progs/tests/func/calls_inside_calls.sy
@@ -0,0 +1,11 @@
+start :: fn {
+    one := fn -> int {
+        ret 1
+    }
+    add := fn a: int, b: int -> int {
+        ret a + b
+    }
+    add(one(), one()) <=> 2
+    add(add(one(), one()), one()) <=> 3
+    add(one(), add(one(), one())) <=> 3
+}
diff --git a/progs/tests/func/exclamation_calling.sy b/progs/tests/func/exclamation_calling.sy
new file mode 100644
index 0000000..02dd81d
--- /dev/null
+++ b/progs/tests/func/exclamation_calling.sy
@@ -0,0 +1,5 @@
+start :: fn {
+    f := fn {}
+    f!
+
+}
diff --git a/progs/tests/func/inner_simple.sy b/progs/tests/func/inner_simple.sy
new file mode 100644
index 0000000..14a6534
--- /dev/null
+++ b/progs/tests/func/inner_simple.sy
@@ -0,0 +1,4 @@
+start :: fn {
+    f := fn {}
+    f()
+}
diff --git a/progs/tests/func/multiple_returns.sy b/progs/tests/func/multiple_returns.sy
new file mode 100644
index 0000000..6cb5e1a
--- /dev/null
+++ b/progs/tests/func/multiple_returns.sy
@@ -0,0 +1,12 @@
+start :: fn {
+    f := fn a: int -> int {
+        if a == 1 {
+            ret 2
+        } else {
+            ret 3
+        }
+    }
+    f(0) <=> 3
+    f(1) <=> 2
+    f(2) <=> 3
+}
diff --git a/progs/tests/func/one_arg.sy b/progs/tests/func/one_arg.sy
new file mode 100644
index 0000000..e7dee83
--- /dev/null
+++ b/progs/tests/func/one_arg.sy
@@ -0,0 +1,5 @@
+start :: fn {
+    f := fn a:int { a <=> 1 }
+    f! 1
+
+}
diff --git a/progs/tests/func/param_1.sy b/progs/tests/func/param_1.sy
new file mode 100644
index 0000000..c96089e
--- /dev/null
+++ b/progs/tests/func/param_1.sy
@@ -0,0 +1,4 @@
+start :: fn {
+    f := fn a: int {}
+    f(1)
+}
diff --git a/progs/tests/func/param_2.sy b/progs/tests/func/param_2.sy
new file mode 100644
index 0000000..1915c42
--- /dev/null
+++ b/progs/tests/func/param_2.sy
@@ -0,0 +1,7 @@
+start :: fn {
+    add := fn a: int, b: int -> int {
+        ret a + b
+    }
+    add(1, 1) <=> 2
+    add(10, 20) <=> 30
+}
diff --git a/progs/tests/func/param_and_return.sy b/progs/tests/func/param_and_return.sy
new file mode 100644
index 0000000..2752fcc
--- /dev/null
+++ b/progs/tests/func/param_and_return.sy
@@ -0,0 +1,7 @@
+start :: fn {
+    f := fn a: int -> int {
+        ret a * 2
+    }
+    f(1) <=> 2
+    f(5) <=> 10
+}
diff --git a/progs/tests/func/passing_functions_as_arguments.sy b/progs/tests/func/passing_functions_as_arguments.sy
new file mode 100644
index 0000000..e09a125
--- /dev/null
+++ b/progs/tests/func/passing_functions_as_arguments.sy
@@ -0,0 +1,9 @@
+start :: fn {
+    g := fn -> int {
+        ret 1
+    }
+    f := fn inner: fn -> int -> int {
+        ret inner()
+    }
+    f(g) <=> 1
+}
diff --git a/progs/tests/func/passing_functions_as_arguments_mixed.sy b/progs/tests/func/passing_functions_as_arguments_mixed.sy
new file mode 100644
index 0000000..b08128e
--- /dev/null
+++ b/progs/tests/func/passing_functions_as_arguments_mixed.sy
@@ -0,0 +1,9 @@
+start :: fn {
+    g := fn a: int -> int {
+        ret a * 2
+    }
+    f := fn inner: fn int -> int, a: int -> int {
+        ret inner(a)
+    }
+    f(g, 2) <=> 4
+}
diff --git a/progs/tests/func/precedence.sy b/progs/tests/func/precedence.sy
new file mode 100644
index 0000000..ae08e05
--- /dev/null
+++ b/progs/tests/func/precedence.sy
@@ -0,0 +1,8 @@
+start :: fn {
+    f := fn a: int, b: int -> int {
+        ret a + b
+    }
+    1 + f(2, 3) <=> 6
+    2 * f(2, 3) <=> 10
+    f(2, 3) - (2 + 3) <=> 0
+}
diff --git a/progs/tests/func/return_1.sy b/progs/tests/func/return_1.sy
new file mode 100644
index 0000000..533208f
--- /dev/null
+++ b/progs/tests/func/return_1.sy
@@ -0,0 +1,6 @@
+start :: fn {
+    f := fn -> int {
+        ret 1
+    }
+    f() <=> 1
+}
diff --git a/progs/tests/func/returning_closures.sy b/progs/tests/func/returning_closures.sy
new file mode 100644
index 0000000..4d69d5a
--- /dev/null
+++ b/progs/tests/func/returning_closures.sy
@@ -0,0 +1,24 @@
+start :: fn {
+
+    f : fn -> fn -> int = fn -> fn -> int {
+        x : int = 0
+        f := fn -> int {
+            x = x + 1
+            ret x
+        }
+        f() <=> 1
+        ret f
+    }
+
+    a := f()
+    b := f()
+
+    a() <=> 2
+    a() <=> 3
+
+    b() <=> 2
+    b() <=> 3
+
+    a() <=> 4
+
+}
diff --git a/progs/tests/func/three_arg.sy b/progs/tests/func/three_arg.sy
new file mode 100644
index 0000000..56eb634
--- /dev/null
+++ b/progs/tests/func/three_arg.sy
@@ -0,0 +1,5 @@
+start :: fn {
+    f := fn a:int, b:int, c:int { c <=> 13 }
+    f! 1, 1 + 2, 1 + 4 * 3
+
+}
diff --git a/progs/tests/func/two_arg.sy b/progs/tests/func/two_arg.sy
new file mode 100644
index 0000000..09ea1f7
--- /dev/null
+++ b/progs/tests/func/two_arg.sy
@@ -0,0 +1,5 @@
+start :: fn {
+    f := fn a:int, b:int { b <=> 3 }
+    f! 1, 1 + 2
+
+}
diff --git a/progs/tests/func/uncallable_type.sy b/progs/tests/func/uncallable_type.sy
new file mode 100644
index 0000000..dbe6e81
--- /dev/null
+++ b/progs/tests/func/uncallable_type.sy
@@ -0,0 +1,8 @@
+start :: fn {
+    f := fn i: int {
+        i()
+    }
+    f
+}
+
+// errors: [ErrorKind::InvalidProgram]
diff --git a/progs/tests/func/wrong_params.sy b/progs/tests/func/wrong_params.sy
new file mode 100644
index 0000000..0082a3a
--- /dev/null
+++ b/progs/tests/func/wrong_params.sy
@@ -0,0 +1,7 @@
+start :: fn {
+
+    f : fn -> int = fn a: int -> int {}
+    f
+}
+
+// errors: [ErrorKind::TypeMismatch(_, _), ErrorKind::TypeMismatch(Type::Int, Type::Void)]
diff --git a/progs/tests/func/wrong_ret.sy b/progs/tests/func/wrong_ret.sy
new file mode 100644
index 0000000..6c4a9a5
--- /dev/null
+++ b/progs/tests/func/wrong_ret.sy
@@ -0,0 +1,7 @@
+start :: fn {
+
+    f : fn -> int = fn {}
+    f
+}
+
+// errors: [ErrorKind::TypeMismatch(_, _)]