Ensure that we are *actually* able to compile without PG

While the tests were passing previously, we didn't actually build if you
compiled without libpq installed on your system. This corrects those
issues, and the failures that resulted from it. There are several places
where I'm legitimately unsure how the code compiled before this change.

I've had to do some janky things to codegen to make it actually work, as
there's an issue where cfg attrs aren't properly applied inside of
`include!`. This is why the dummy version has to exist, and why it warns
instead of errors. It might make sense to just define the macro as a
no-op in the future.

Author: sgrif

.travis.yml

@@ -43,7 +43,7 @@ matrix:
   allow_failures:
     - rust: nightly
 after_success:
-  - "(cd diesel && travis-cargo --only stable doc-upload -- --features \"postgres sqlite\")"
+  - "(cd diesel && travis-cargo --only stable doc-upload)"
 branches:
   only:
     - master

diesel_codegen/Cargo.toml

@@ -17,12 +17,13 @@ syntex_syntax = { version = "^0.26.0", optional = true }
 [dependencies]
 syntex = { version = "^0.26.0", optional = true }
 syntex_syntax = { version = "^0.26.0", optional = true }
-diesel = { git = "https://github.com/sgrif/diesel.git" }
+diesel = { path = "../diesel", default-features = false }
 
 [features]
-default = ["with-syntex"]
+default = ["with-syntex", "postgres"]
 nightly = []
 with-syntex = ["syntex", "syntex_syntax"]
+postgres = ["diesel/postgres"]
 
 [lib]
 name = "diesel_codegen"

diesel_codegen/src/dummy_schema_inference.rs

@@ -0,0 +1,21 @@
+use syntax::ast;
+use syntax::codemap::Span;
+use syntax::ext::base::*;
+
+pub fn expand_load_table<'cx>(
+    cx: &'cx mut ExtCtxt,
+    sp: Span,
+    _tts: &[ast::TokenTree]
+) -> Box<MacResult+'cx> {
+    cx.span_warn(sp, "load_table_from_schema! is only supported on PostgreSQL");
+    DummyResult::any(sp)
+}
+
+pub fn expand_infer_schema<'cx>(
+    cx: &'cx mut ExtCtxt,
+    sp: Span,
+    _tts: &[ast::TokenTree]
+) -> Box<MacResult+'cx> {
+    cx.span_warn(sp, "infer_schema! is only supported on PostgreSQL");
+    DummyResult::any(sp)
+}

diesel_codegen/src/lib.in.rs

@@ -3,5 +3,10 @@ mod attr;
 mod insertable;
 mod model;
 mod queryable;
+#[cfg(feature = "postgres")]
 mod schema_inference;
+#[cfg(not(feature = "postgres"))]
+#[path="dummy_schema_inference.rs"]
+mod schema_inference;
+
 mod update;

diesel_tests/Cargo.toml

@@ -9,7 +9,7 @@ build = "build.rs"
 syntex = { version = "^0.26.0", optional = true }
 diesel_codegen = { path = "../diesel_codegen", default-features = false }
 dotenv_codegen = { git = "https://github.com/slapresta/rust-dotenv.git",  optional = true }
-diesel = { path = "../diesel" }
+diesel = { path = "../diesel", default-features = false }
 dotenv = { git = "https://github.com/slapresta/rust-dotenv.git" }
 
 [dependencies]
@@ -26,7 +26,7 @@ quickcheck = { git = "https://github.com/BurntSushi/quickcheck.git" }
 default = ["syntex", "diesel_codegen/with-syntex", "dotenv_codegen"]
 unstable = ["compiletest_rs", "diesel_codegen/nightly", "diesel/unstable",
   "quickcheck/unstable", "dotenv_macros"]
-postgres = ["diesel/postgres"]
+postgres = ["diesel/postgres", "diesel_codegen/postgres"]
 sqlite = ["diesel/sqlite"]
 
 [[test]]

diesel_tests/build.rs

@@ -25,19 +25,33 @@ mod inner {
     pub fn main() {}
 }
 
-extern crate diesel;
-extern crate dotenv;
-use diesel::*;
-use diesel::pg::PgConnection;
-use dotenv::dotenv;
-use std::io;
+#[cfg(feature = "postgres")]
+mod outer {
+    extern crate diesel;
+    extern crate dotenv;
+    use self::diesel::*;
+    use self::diesel::pg::PgConnection;
+    use self::dotenv::dotenv;
+    use std::io;
+
+    pub fn main() {
+        dotenv().ok();
+        let database_url = ::std::env::var("DATABASE_URL")
+            .expect("DATABASE_URL must be set to run tests");
+        let connection = PgConnection::establish(&database_url).unwrap();
+        let migrations_dir = migrations::find_migrations_directory().unwrap().join("postgresql");
+        migrations::run_pending_migrations_in_directory(&connection, &migrations_dir, &mut io::sink()).unwrap();
+        ::inner::main();
+    }
+}
+
+#[cfg(not(feature = "postgres"))]
+mod outer {
+    pub fn main() {
+        ::inner::main();
+    }
+}
 
 fn main() {
-    dotenv().ok();
-    let database_url = ::std::env::var("DATABASE_URL")
-        .expect("DATABASE_URL must be set to run tests");
-    let connection = PgConnection::establish(&database_url).unwrap();
-    let migrations_dir = migrations::find_migrations_directory().unwrap().join("postgresql");
-    migrations::run_pending_migrations_in_directory(&connection, &migrations_dir, &mut io::sink()).unwrap();
-    inner::main();
+    outer::main();
 }

diesel_tests/tests/annotations.rs

@@ -94,13 +94,13 @@ mod associations_can_have_nullable_foreign_keys {
 
     table! {
         foos{
-            id -> Serial,
+            id -> Integer,
         }
     }
 
     table! {
         bars {
-            id -> Serial,
+            id -> Integer,
             foo_id -> Nullable<Integer>,
         }
     }

diesel_tests/tests/compile-fail/global/cannot_mix_aggregate_and_non_aggregate_selects.rs

@@ -6,7 +6,7 @@ use diesel::expression::count;
 
 table! {
     users {
-        id -> Serial,
+        id -> Integer,
     }
 }
 

diesel_tests/tests/compile-fail/global/cannot_pass_aggregate_to_where.rs

@@ -6,7 +6,7 @@ use diesel::expression::count;
 
 table! {
     users {
-        id -> Serial,
+        id -> Integer,
     }
 }
 

diesel_tests/tests/compile-fail/global/expressions_can_only_be_compared_for_equality_to_expressions_of_same_type.rs

@@ -5,7 +5,7 @@ use diesel::*;
 
 table! {
     users {
-        id -> Serial,
+        id -> Integer,
         name -> VarChar,
     }
 }