From 323094f418c7d3b056847debd5d7ebd240889111 Mon Sep 17 00:00:00 2001
From: Joshua Lampert <joshua.lampert@uni-hamburg.de>
Date: Mon, 20 Nov 2023 13:50:39 +0100
Subject: [PATCH] throw error in trixi_include when assignment is not found

---
 src/util.jl | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/src/util.jl b/src/util.jl
index df7d7378..1dc2168d 100644
--- a/src/util.jl
+++ b/src/util.jl
@@ -96,6 +96,16 @@ julia> redirect_stdout(devnull) do
 ```
 """
 function trixi_include(mod::Module, example::AbstractString; kwargs...)
+    # Check that all kwargs exist as assignments
+    code = read(example, String)
+    expr = Meta.parse("begin \n$code \nend")
+    expr = insert_maxiters(expr)
+
+    for (key, val) in kwargs
+        # This will throw an error when `key` is not found
+        find_assignment(expr, key)
+    end
+
     Base.include(ex -> replace_assignments(insert_maxiters(ex); kwargs...), mod, example)
 end
 
@@ -282,6 +292,7 @@ end
 function find_assignment(expr, destination)
     # declare result to be able to assign to it in the closure
     local result
+    found = false
 
     # find explicit and keyword assignments
     walkexpr(expr) do x
@@ -289,12 +300,17 @@ function find_assignment(expr, destination)
             if (x.head === Symbol("=") || x.head === :kw) &&
                x.args[1] === Symbol(destination)
                 result = x.args[2]
+                found = true
                 # dump(x)
             end
         end
         return x
     end
 
+    if !found
+        throw(ArgumentError("assignment `$destination` not found in expression"))
+    end
+
     result
 end