Bump crates to 2018 edition

The problem with bad diagnostics appears to have been due to not being able to find the macro to emit compile errors.

derive_builder/Cargo.toml

@@ -1,10 +1,13 @@
 [package]
 name = "derive_builder"
 version = "0.13.0"
-authors = ["Colin Kiegel <[email protected]>",
-           "Pascal Hertleif <[email protected]>",
-           "Jan-Erik Rediger <[email protected]>",
-           "Ted Driggs <[email protected]>"]
+authors = [
+    "Colin Kiegel <[email protected]>",
+    "Pascal Hertleif <[email protected]>",
+    "Jan-Erik Rediger <[email protected]>",
+    "Ted Driggs <[email protected]>",
+]
+edition = "2018"
 
 description = "Rust macro to automatically implement the builder pattern for arbitrary structs."
 repository = "https://github.com/colin-kiegel/rust-derive-builder"
@@ -31,4 +34,4 @@ serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 
 [target.'cfg(compiletests)'.dev-dependencies]
-trybuild = "1.0.38"
+trybuild = "1.0.38"

derive_builder/src/lib.rs

@@ -728,7 +728,7 @@ pub use error::UninitializedFieldError;
 pub mod export {
     pub mod core {
         #[cfg(feature = "alloc")]
-        pub use alloc::string;
+        pub use ::alloc::string;
         #[cfg(not(feature = "std"))]
         pub use core::*;
         #[cfg(feature = "std")]

derive_builder_core/Cargo.toml

@@ -7,7 +7,7 @@ authors = [
     "Jan-Erik Rediger <[email protected]>",
     "Ted Driggs <[email protected]>",
 ]
-
+edition = "2018"
 description = "Internal helper library for the derive_builder crate."
 repository = "https://github.com/colin-kiegel/rust-derive-builder"
 documentation = "https://docs.rs/derive_builder_core"

derive_builder_core/src/build_method.rs

@@ -1,15 +1,12 @@
 use std::borrow::Cow;
 
-use doc_comment_from;
 use proc_macro2::{Span, TokenStream};
 use quote::{ToTokens, TokenStreamExt};
-use syn;
 use syn::spanned::Spanned;
-use BuilderPattern;
-use Initializer;
-use DEFAULT_STRUCT_NAME;
 
-use crate::DefaultExpression;
+use crate::{
+    doc_comment_from, BuilderPattern, DefaultExpression, Initializer, DEFAULT_STRUCT_NAME,
+};
 
 /// Initializer for the struct fields in the build method, implementing
 /// `quote::ToTokens`.

derive_builder_core/src/builder.rs

@@ -5,12 +5,9 @@ use quote::{format_ident, ToTokens, TokenStreamExt};
 use syn::punctuated::Punctuated;
 use syn::{self, Path, TraitBound, TraitBoundModifier, TypeParamBound};
 
-use doc_comment_from;
-use BuildMethod;
-use BuilderField;
-use BuilderPattern;
-use DeprecationNotes;
-use Setter;
+use crate::{
+    doc_comment_from, BuildMethod, BuilderField, BuilderPattern, DeprecationNotes, Setter,
+};
 
 const ALLOC_NOT_ENABLED_ERROR: &str = r#"`alloc` is disabled within 'derive_builder', consider one of the following:
 * enable feature `alloc` on 'dervie_builder' if a `global_allocator` is present

derive_builder_core/src/builder_field.rs

@@ -2,7 +2,6 @@ use std::borrow::Cow;
 
 use proc_macro2::TokenStream;
 use quote::{ToTokens, TokenStreamExt};
-use syn;
 
 /// Field for the builder struct, implementing `quote::ToTokens`.
 ///

derive_builder_core/src/deprecation_notes.rs

@@ -1,6 +1,5 @@
 use proc_macro2::{Span, TokenStream};
 use quote::{ToTokens, TokenStreamExt};
-use syn;
 
 /// Deprecation notes we want to emit to the user, implementing
 /// `quote::ToTokens`.

derive_builder_core/src/initializer.rs

@@ -1,10 +1,7 @@
 use proc_macro2::{Span, TokenStream};
 use quote::{ToTokens, TokenStreamExt};
-use syn;
-use BuilderPattern;
-use DEFAULT_STRUCT_NAME;
 
-use crate::{change_span, BlockContents, DefaultExpression};
+use crate::{change_span, BlockContents, BuilderPattern, DefaultExpression, DEFAULT_STRUCT_NAME};
 
 /// Initializer for the target struct fields, implementing `quote::ToTokens`.
 ///

derive_builder_core/src/setter.rs

@@ -3,12 +3,8 @@ use std::borrow::Cow;
 
 use proc_macro2::{Span, TokenStream};
 use quote::{ToTokens, TokenStreamExt};
-use syn;
 
-use BuilderFieldType;
-use BuilderPattern;
-use DeprecationNotes;
-use Each;
+use crate::{BuilderFieldType, BuilderPattern, DeprecationNotes, Each};
 
 /// Setter for the struct fields in the build method, implementing
 /// `quote::ToTokens`.

derive_builder_macro/Cargo.toml

@@ -7,6 +7,7 @@ authors = [
     "Jan-Erik Rediger <[email protected]>",
     "Ted Driggs <[email protected]>",
 ]
+edition = "2018"
 
 description = "Rust macro to automatically implement the builder pattern for arbitrary structs."
 repository = "https://github.com/colin-kiegel/rust-derive-builder"