Fix indentation of module with expression as module name

src/runestone.jl

@@ -2169,17 +2169,23 @@ function indent_module(ctx::Context, node::Node)
         kids[mod_idx] = add_tag(mod_node, TAG_INDENT)
         any_kid_changed = true
     end
-    # Second node is the space between keyword and name
-    # TODO: Make sure there is just a single space
+    # Next we expect whitespace + identifier, but can also be expression with whitespace
+    # hidden inside...
     space_idx = 2
     space_node = kids[space_idx]
-    @assert is_leaf(space_node) && kind(space_node) === K"Whitespace"
-    # Third node is the module identifier
+    if kind(space_node) === K"Whitespace"
+        # Now we need an identifier or var"
         id_idx = 3
         id_node = kids[id_idx]
         @assert kind(id_node) in KSet"Identifier var"
-    # Fourth node is the module body block.
         block_idx = 4
+    else
+        # This can be reached if the module name is interpolated for example
+        @assert kind(first_leaf(space_node)) === K"Whitespace"
+        @assert !JuliaSyntax.is_whitespace(space_node)
+        block_idx = 3
+    end
+    # Next node is the module body block.
     block_node′ = indent_block(ctx, kids[block_idx])
     if block_node′ !== nothing
         kids[block_idx] = block_node′

test/runtests.jl

@@ -600,6 +600,11 @@ end
             # var"" as module name
             @test format_string("$(b)module var\"A\"\n$(sp)x\n$(sp)end\nf") ==
                 "$(b)module var\"A\"\n    x\nend\nf"
+            # interpolated module name
+            @test format_string("$(b)module \$A\n$(sp)x\n$(sp)end\nf") ==
+                "$(b)module \$A\n    x\nend\nf"
+            @test format_string("$(b)module \$(A)\n$(sp)x\n$(sp)end\nf") ==
+                "$(b)module \$(A)\n    x\nend\nf"
             # single line module
             @test format_string("$(b)module A; x; end\nf") == "$(b)module A; x; end\nf"
         end