cleanCargoToml: do not strip edition fields

* The edition entries can affect cargo behavior, not just rustc
  behavior, so we should keep them in for consistency with what the
  project expects

checks/cleanCargoToml/complex/Cargo.toml

@@ -42,7 +42,7 @@ doc = true
 plugin = false
 proc-macro = false
 harness = true
-edition = "2015"
+edition = "2021"
 crate-type = ["lib"]
 required-features = ["libfeature1", "libfeature2"]
 
@@ -69,7 +69,7 @@ doc = true
 plugin = false
 proc-macro = false
 harness = true
-edition = "2015"
+edition = "2018"
 required-features = ["bin2feature1", "bin2feature2"]
 
 [[example]]
@@ -95,7 +95,7 @@ doc = true
 plugin = false
 proc-macro = false
 harness = true
-edition = "2015"
+edition = "2018"
 required-features = ["example2feature1", "example2feature2"]
 
 [[test]]
@@ -121,7 +121,7 @@ doc = true
 plugin = false
 proc-macro = false
 harness = true
-edition = "2015"
+edition = "2018"
 required-features = ["test2feature1", "test2feature2"]
 
 [[bench]]
@@ -147,7 +147,7 @@ doc = true
 plugin = false
 proc-macro = false
 harness = true
-edition = "2015"
+edition = "2018"
 required-features = ["bench2feature1", "bench2feature2"]
 
 [dependencies]

checks/cleanCargoToml/complex/expected.toml

@@ -26,11 +26,13 @@ barfeature = ["foofeature"]
 foofeature = []
 
 [lib]
+edition = "2021"
 name = "foo"
 path = "/nix/store/dummy.rs"
 required-features = ["libfeature1", "libfeature2"]
 
 [package]
+edition = "2021"
 name = "some name"
 version = "1.2.3"
 workspace = "some/path/to/workspace"
@@ -77,41 +79,49 @@ exclude = ["crates/foo", "path/to/other"]
 members = ["member1", "path/to/member2", "crates/*"]
 
 [[bench]]
+edition = "2015"
 name = "bench1"
 path = "/nix/store/dummy.rs"
 required-features = ["bench1feature1", "bench1feature2"]
 
 [[bench]]
+edition = "2018"
 name = "bench2"
 path = "/nix/store/dummy.rs"
 required-features = ["bench2feature1", "bench2feature2"]
 
 [[bin]]
+edition = "2015"
 name = "bin1"
 path = "/nix/store/dummy.rs"
 required-features = ["bin1feature1", "bin1feature2"]
 
 [[bin]]
+edition = "2018"
 name = "bin2"
 path = "/nix/store/dummy.rs"
 required-features = ["bin2feature1", "bin2feature2"]
 
 [[example]]
+edition = "2015"
 name = "example1"
 path = "/nix/store/dummy.rs"
 required-features = ["example1feature1", "example1feature2"]
 
 [[example]]
+edition = "2018"
 name = "example2"
 path = "/nix/store/dummy.rs"
 required-features = ["example2feature1", "example2feature2"]
 
 [[test]]
+edition = "2015"
 name = "test1"
 path = "/nix/store/dummy.rs"
 required-features = ["test1feature1", "test1feature2"]
 
 [[test]]
+edition = "2018"
 name = "test2"
 path = "/nix/store/dummy.rs"
 required-features = ["test2feature1", "test2feature2"]

lib/cleanCargoToml.nix

@@ -1,5 +1,4 @@
 { fromTOML
-, toTOML
 , writeText
 }:
 
@@ -23,7 +22,6 @@ let
     "default-run"
     "description"
     "documentation"
-    "edition"
     "exclude"
     "homepage"
     "include"
@@ -40,9 +38,10 @@ let
 
     # Additional package attributes which are expressly kept in
     # (but listed here for audit purposes)
-    # "name"         # The name of the package.
-    # "version"      # The version of the package.
-    # "workspace"    # Path to the workspace for the package.
+    # "edition"      # Influences cargo behavior
+    # "name"         # Required
+    # "version"      # Required
+    # "workspace"    # Keep project structure as is
   ];
 
   # https://doc.rust-lang.org/cargo/reference/cargo-targets.html#configuring-a-target
@@ -54,7 +53,6 @@ let
           "doctest"
           "bench"
           "doc"
-          "edition"
           "plugin"
           "proc-macro"
           "harness"
@@ -62,6 +60,7 @@ let
 
           # Additional package attributes which are expressly kept in
           # (but listed here for audit purposes)
+          # "edition"           # Influences cargo behavior
           # "name"              # let cargo manage targets/collisions/etc.
           # "required-features" # influences dependency feature combinations
         ];