Fix failing compile tests

I've also renamed `ContainsTable` to `AppearsInFromClause`, as the error
message complaining that `users: AppearsInFromClause<posts>` is not
satisfied is much clearer.

Author: sgrif

diesel/src/macros/mod.rs

@@ -27,24 +27,24 @@ macro_rules! __diesel_column {
         }
 
         impl<QS> AppearsOnTable<QS> for $column_name where
-            QS: ContainsTable<$($table)::*, Count=Once>,
+            QS: AppearsInFromClause<$($table)::*, Count=Once>,
         {
         }
 
         impl<Left, Right> SelectableExpression<
             Join<Left, Right, LeftOuter>,
         > for $column_name where
             $column_name: AppearsOnTable<Join<Left, Right, LeftOuter>>,
-            Left: ContainsTable<$($table)::*, Count=Once>,
-            Right: ContainsTable<$($table)::*, Count=Never>,
+            Left: AppearsInFromClause<$($table)::*, Count=Once>,
+            Right: AppearsInFromClause<$($table)::*, Count=Never>,
         {
         }
 
         impl<Left, Right> SelectableExpression<
             Join<Left, Right, Inner>,
         > for $column_name where
             $column_name: AppearsOnTable<Join<Left, Right, Inner>>,
-            Join<Left, Right, Inner>: ContainsTable<$($table)::*, Count=Once>,
+            Join<Left, Right, Inner>: AppearsInFromClause<$($table)::*, Count=Once>,
         {
         }
 
@@ -323,7 +323,7 @@ macro_rules! table_body {
             use $crate::associations::HasTable;
             use $crate::query_builder::*;
             use $crate::query_builder::nodes::Identifier;
-            use $crate::query_source::{ContainsTable, Once};
+            use $crate::query_source::{AppearsInFromClause, Once};
             $(use $($import)::+;)+
             pub use self::columns::*;
 
@@ -403,7 +403,7 @@ macro_rules! table_body {
                 }
             }
 
-            impl ContainsTable<table> for table {
+            impl AppearsInFromClause<table> for table {
                 type Count = Once;
             }
 
@@ -416,7 +416,7 @@ macro_rules! table_body {
                 use $crate::backend::Backend;
                 use $crate::query_builder::{QueryFragment, AstPass};
                 use $crate::query_source::joins::{Join, JoinOn, Inner, LeftOuter};
-                use $crate::query_source::{ContainsTable, Once, Never};
+                use $crate::query_source::{AppearsInFromClause, Once, Never};
                 use $crate::result::QueryResult;
                 $(use $($import)::+;)+
 
@@ -524,7 +524,7 @@ macro_rules! joinable_inner {
         primary_key_ty = $primary_key_ty:ty,
         primary_key_expr = $primary_key_expr:expr,
     ) => {
-        impl $crate::query_source::ContainsTable<$right_table_ty> for $left_table_ty {
+        impl $crate::query_source::AppearsInFromClause<$right_table_ty> for $left_table_ty {
             type Count = $crate::query_source::Never;
         }
         impl $crate::JoinTo<$right_table_ty> for $left_table_ty {

diesel/src/query_source/joins.rs

@@ -175,18 +175,18 @@ impl<DB: Backend> QueryFragment<DB> for LeftOuter {
     }
 }
 
-use super::{Succ, Never, ContainsTable};
+use super::{Succ, Never, AppearsInFromClause};
 
-impl<T, Left, Right, Kind> ContainsTable<T> for Join<Left, Right, Kind> where
-    Left: ContainsTable<T>,
-    Right: ContainsTable<T>,
+impl<T, Left, Right, Kind> AppearsInFromClause<T> for Join<Left, Right, Kind> where
+    Left: AppearsInFromClause<T>,
+    Right: AppearsInFromClause<T>,
     Left::Count: Plus<Right::Count>,
 {
     type Count = <Left::Count as Plus<Right::Count>>::Output;
 }
 
-impl<T, Join, On> ContainsTable<T> for JoinOn<Join, On> where
-    Join: ContainsTable<T>,
+impl<T, Join, On> AppearsInFromClause<T> for JoinOn<Join, On> where
+    Join: AppearsInFromClause<T>,
 {
     type Count = Join::Count;
 }

diesel/src/query_source/mod.rs

@@ -49,7 +49,7 @@ pub trait Table: QuerySource + AsQuery + Sized {
     fn all_columns() -> Self::AllColumns;
 }
 
-pub trait ContainsTable<QS> {
+pub trait AppearsInFromClause<QS> {
     type Count;
 }
 

diesel_compile_tests/tests/compile-fail/aggregate_expression_requires_column_from_same_table.rs

@@ -19,14 +19,14 @@ fn main() {
     use diesel::expression::dsl::*;
     let source = users::table.select(sum(posts::id));
     //~^ ERROR E0277
-    //~| ERROR AppearsOnTable
+    //~| ERROR AppearsInFromClause
     let source = users::table.select(avg(posts::id));
     //~^ ERROR E0277
-    //~| ERROR AppearsOnTable
+    //~| ERROR AppearsInFromClause
     let source = users::table.select(max(posts::id));
     //~^ ERROR E0277
-    //~| ERROR AppearsOnTable
+    //~| ERROR AppearsInFromClause
     let source = users::table.select(min(posts::id));
     //~^ ERROR E0277
-    //~| ERROR AppearsOnTable
+    //~| ERROR AppearsInFromClause
 }

diesel_compile_tests/tests/compile-fail/boxed_queries_require_selectable_expression_for_filter.rs

@@ -20,5 +20,5 @@ table! {
 
 fn main() {
     users::table.into_boxed::<Pg>().filter(posts::title.eq("Hello"));
-    //~^ ERROR AppearsOnTable
+    //~^ ERROR AppearsInFromClause
 }

diesel_compile_tests/tests/compile-fail/boxed_queries_require_selectable_expression_for_order.rs

@@ -20,5 +20,5 @@ table! {
 
 fn main() {
     users::table.into_boxed::<Pg>().order(posts::title.desc());
-    //~^ ERROR AppearsOnTable
+    //~^ ERROR AppearsInFromClause
 }

diesel_compile_tests/tests/compile-fail/custom_returning_requires_selectable_expression.rs

@@ -36,5 +36,5 @@ fn main() {
     };
     let stmt = insert(&new_user).into(users).returning((name, bad::age));
     //~^ ERROR SelectableExpression
-    //~| ERROR AppearsOnTable
+    //~| ERROR AppearsInFromClause
 }

diesel_compile_tests/tests/compile-fail/filter_cannot_take_comparison_for_columns_from_another_table.rs

@@ -19,7 +19,7 @@ table! {
 
 fn main() {
     let _ = users::table.filter(posts::id.eq(1));
-    //~^ ERROR AppearsOnTable
+    //~^ ERROR AppearsInFromClause
     let _ = users::table.filter(users::name.eq(posts::title));
-    //~^ ERROR AppearsOnTable
+    //~^ ERROR AppearsInFromClause
 }

diesel_compile_tests/tests/compile-fail/right_side_of_left_join_requires_nullable.rs

@@ -27,13 +27,17 @@ fn main() {
     let join = users::table.left_outer_join(posts::table);
 
     // Invalid, only Nullable<title> is selectable
-    let _ = join.select(posts::title); //~ ERROR E0277
+    let _ = join.select(posts::title);
+    //~^ ERROR E0271
+    //~| ERROR E0271
     // Valid
     let _ = join.select(posts::title.nullable());
     // Valid -- NULL to a function will return null
     let _ = join.select(lower(posts::title).nullable());
     // Invalid, only Nullable<title> is selectable
-    let _ = join.select(lower(posts::title)); //~ ERROR E0277
+    let _ = join.select(lower(posts::title));
+    //~^ ERROR E0271
+    //~| ERROR E0271
     // Invalid, Nullable<title> is selectable, but lower expects not-null
     let _ = join.select(lower(posts::title.nullable())); //~ ERROR E0271
 }

diesel_compile_tests/tests/compile-fail/selecting_multiple_columns_requires_all_must_be_from_selectable_table.rs

@@ -23,7 +23,6 @@ fn main() {
     //~^ ERROR Selectable
     //~| ERROR E0277
     //~| ERROR E0277
-    //~| ERROR E0277
     let stuff = users::table.select((posts::id, users::name));
     //~^ ERROR Selectable
     //~| ERROR E0277