make tools/draw_graph.sh work again

Cargo.toml

@@ -24,3 +24,5 @@ import = { path = "import" }
 [[bin]]
 path = "pbtc/main.rs"
 name = "pbtc"
+
+[workspace]

tools/draw_graph.sh

@@ -1,4 +1,16 @@
 #!/bin/bash
 
-cargo graph --build-shape box --build-line-style dashed > graph.dot
-dot -Tpng > graph.png graph.dot
+# Cargo graph does not work with cargo worspaces #33
+# https://github.com/kbknapp/cargo-graph/issues/33
+# so first we need to patch Cargo.toml and remove workspace
+patch -R Cargo.toml tools/workspace.diff
+
+# Now let's rebuild Cargo.lock by telling cargo to update local package
+cargo update -p pbtc
+
+# And draw dependencies graph using cargo graph
+cargo graph --build-shape box --build-line-style dashed > tools/graph.dot
+dot -Tpng > tools/graph.png tools/graph.dot
+
+# Finally let's bring back old Cargo.toml file
+patch Cargo.toml tools/workspace.diff

tools/workspace.diff

@@ -0,0 +1,10 @@
+diff --git Cargo.toml Cargo.toml
+index fca51d5..6a16dd6 100644
+--- Cargo.toml
++++ Cargo.toml
+@@ -24,3 +24,5 @@ import = { path = "import" }
+ [[bin]]
+ path = "pbtc/main.rs"
+ name = "pbtc"
++
++[workspace]