Fix incorrect column names for SELECT * preceded by a WITH

In  stephencelis#1139 I introduced support for the `WITH` clause. My implementation contains a bug: the statement preparer doesn't produce the correct result column names for queries containing a `SELECT *` preceded by a `WITH`.

For example, consider the following statement:

```
WITH temp AS ( SELECT id, email from users) SELECT * from temp
```

An error would be thrown when preparing this statement because the glob expansion procedure would try to look up the column names for the result by looking up the column names for the query `SELECT * from temp`. This does not work because `temp` is a temporary view defined in the `WITH` clause.

To fix this, I modified the glob expansion procedure to include the `WITH` clause in the query used to look up the result column names.

Author: marmphco

Sources/SQLite/Typed/Query.swift

@@ -1036,10 +1036,29 @@ extension Connection {
             let column = names.removeLast()
             let namespace = names.joined(separator: ".")
 
+            // Return a copy of the input "with" clause stripping all subclauses besides "select", "join", and "with".
+            func strip(_ with: WithClauses) -> WithClauses {
+                var stripped = WithClauses()
+                stripped.recursive = with.recursive
+                for subclause in with.clauses {
+                    let query = subclause.query
+                    var strippedQuery = type(of: query).init(query.clauses.from.name, database: query.clauses.from.database)
+                    strippedQuery.clauses.select = query.clauses.select
+                    strippedQuery.clauses.join = query.clauses.join
+                    strippedQuery.clauses.with = strip(query.clauses.with)
+
+                    var strippedSubclause = WithClauses.Clause(alias: subclause.alias, query: strippedQuery)
+                    strippedSubclause.columns = subclause.columns
+                    stripped.clauses.append(strippedSubclause)
+                }
+                return stripped
+            }
+
             func expandGlob(_ namespace: Bool) -> (QueryType) throws -> Void {
                 { (queryType: QueryType) throws -> Void in
                     var query = type(of: queryType).init(queryType.clauses.from.name, database: queryType.clauses.from.database)
                     query.clauses.select = queryType.clauses.select
+                    query.clauses.with = strip(queryType.clauses.with)
                     let expression = query.expression
                     var names = try self.prepare(expression.template, expression.bindings).columnNames.map { $0.quote() }
                     if namespace { names = names.map { "\(queryType.tableName().expression.template).\($0)" } }

Tests/SQLiteTests/Typed/QueryIntegrationTests.swift

@@ -276,6 +276,39 @@ class QueryIntegrationTests: SQLiteTestCase {
 
         XCTAssertEqual(21, sum)
     }
+
+    /// Verify that `*` is properly expanded in a SELECT statement following a WITH clause.
+    func test_with_glob_expansion() throws {
+        let names = Table("names")
+        let name = Expression<String>("name")
+        try db.run(names.create { builder in
+            builder.column(email)
+            builder.column(name)
+        })
+
+        try db.run(users.insert(email <- "[email protected]"))
+        try db.run(names.insert(email <- "[email protected]", name <- "Alice"))
+
+        // WITH intermediate AS ( SELECT ... ) SELECT * FROM intermediate
+        let intermediate = Table("intermediate")
+        let rows = try db.prepare(
+            intermediate
+                .with(intermediate,
+                      as: users
+                        .select([id, users[email], name])
+                        .join(names, on: names[email] == users[email])
+                        .where(users[email] == "[email protected]")
+                     ))
+
+        // There should be at least one row in the result.
+        let row = try XCTUnwrap(rows.makeIterator().next())
+        
+        // Verify the column names
+        XCTAssertEqual(row.columnNames.count, 3)
+        XCTAssertNotNil(row[id])
+        XCTAssertNotNil(row[name])
+        XCTAssertNotNil(row[email])
+    }
 }
 
 extension Connection {