Check the SQLite analyze cases against sqlite3 in goldeneye, and make sqlc agree with it

CLAUDE.md

@@ -150,8 +150,8 @@ from a live database by `/internal/goldeneye`, a nested module, and its tests
 verify the committed files against one byte for byte. The same module checks
 the `analyze_*` cases under `/internal/endtoend/testdata/` against what the
 database itself reports for them, so a `fixture.sql` next to a case's schema
-gives the queries rows to run against. Engines whose database is not
-available skip.
+gives the queries rows to run against. ClickHouse and SQLite have the check
+today; engines whose database is not available skip.
 
 ```bash
 cd internal/goldeneye

internal/core/analyzer/expr.go

@@ -285,6 +285,12 @@ func (a *analyzer) typeAExpr(e *ast.A_Expr) (exprType, error) {
 	if err != nil {
 		return exprType{}, err
 	}
+	// The postfix null tests SQLite has — x ISNULL, x NOTNULL, x NOT NULL —
+	// arrive as operators with no right operand, and are predicates that
+	// are never NULL.
+	if e.Rexpr == nil && isNullTest(opName) {
+		return a.boolType(false)
+	}
 	rightT, err := a.typeExpr(e.Rexpr)
 	if err != nil {
 		return exprType{}, err
@@ -305,12 +311,25 @@ func (a *analyzer) typeAExpr(e *ast.A_Expr) (exprType, error) {
 	if err != nil {
 		return exprType{}, err
 	}
+	// An operator's result is NULL when an operand is, except for IS and
+	// IS NOT, which test for NULL rather than propagate it: x IS NULL and
+	// x IS y are never NULL, whatever x and y are.
 	return exprType{
 		typeOID:  overload.ResultTypeOID,
-		nullable: leftT.nullable || rightT.nullable,
+		nullable: (leftT.nullable || rightT.nullable) && !isNullTest(opName),
 	}, nil
 }
 
+// isNullTest reports whether an operator compares with NULL as a value
+// rather than propagating it, so that its result is never NULL.
+func isNullTest(opName string) bool {
+	switch opName {
+	case "IS", "IS NOT", "ISNULL", "NOTNULL", "NOT NULL":
+		return true
+	}
+	return false
+}
+
 // typeQuantifiedExpr types "x = ANY($1)" and "x > ALL(...)": the right side
 // holds values of the left side's type, and the result is a predicate.
 func (a *analyzer) typeQuantifiedExpr(e *ast.A_Expr) (exprType, error) {

internal/endtoend/testdata/analyze_expressions/sqlite/exec.json

@@ -0,0 +1,5 @@
+{
+  "command": "analyze",
+  "args": ["--dialect", "sqlite", "--schema", "schema.sql", "query.sql"],
+  "contexts": ["base"]
+}

internal/endtoend/testdata/analyze_expressions/sqlite/fixture.sql

@@ -0,0 +1,4 @@
+INSERT INTO users (id, name, bio, score) VALUES (1, 'ann', NULL, 1.5);
+INSERT INTO users (id, name, bio, score) VALUES (2, 'bob', 'hello', 2.5);
+INSERT INTO posts (id, user_id, title, created) VALUES (1, 1, 'first', '2024-01-01');
+INSERT INTO posts (id, user_id, title, created) VALUES (2, 1, NULL, '2024-01-02');

internal/endtoend/testdata/analyze_expressions/sqlite/query.sql

@@ -0,0 +1,23 @@
+-- name: PostStats :one
+SELECT count(*) AS total, max(id) AS latest, min(created) AS first
+FROM posts WHERE user_id = ?;
+
+-- name: UserScores :one
+SELECT avg(score) AS mean, sum(score) AS sum, sum(id) AS ids, group_concat(name) AS names
+FROM users;
+
+-- name: ListUsers :many
+SELECT id, lower(name) AS lname, id + 1 AS next
+FROM users WHERE id IN (?, ?);
+
+-- name: ListPosts :many
+SELECT id, title FROM posts ORDER BY created LIMIT ? OFFSET ?;
+
+-- name: UserPosts :many
+SELECT u.name, p.title, p.created
+FROM users u LEFT JOIN posts p ON p.user_id = u.id
+WHERE u.name LIKE ? || '%';
+
+-- name: CreatePost :one
+INSERT INTO posts (user_id, title, created) VALUES (?, ?, datetime('now'))
+RETURNING id, created;

internal/endtoend/testdata/analyze_expressions/sqlite/schema.sql

@@ -0,0 +1,15 @@
+CREATE TABLE users (
+  id    INTEGER PRIMARY KEY,
+  name  TEXT NOT NULL,
+  bio   TEXT,
+  score REAL NOT NULL DEFAULT 0
+);
+
+CREATE TABLE posts (
+  id      INTEGER PRIMARY KEY,
+  user_id INTEGER NOT NULL REFERENCES users(id),
+  title   TEXT,
+  created TEXT NOT NULL
+);
+
+CREATE INDEX posts_user ON posts(user_id);

internal/endtoend/testdata/analyze_expressions/sqlite/stdout.json

@@ -0,0 +1,245 @@
+[
+  {
+    "name": "PostStats",
+    "cmd": ":one",
+    "columns": [
+      {
+        "name": "total",
+        "type": {
+          "name": "integer"
+        }
+      },
+      {
+        "name": "latest",
+        "type": {
+          "name": "integer",
+          "nullable": true
+        }
+      },
+      {
+        "name": "first",
+        "type": {
+          "name": "text",
+          "nullable": true
+        }
+      }
+    ],
+    "params": [
+      {
+        "number": 1,
+        "column": {
+          "name": "user_id",
+          "type": {
+            "name": "integer"
+          },
+          "table": "posts"
+        }
+      }
+    ]
+  },
+  {
+    "name": "UserScores",
+    "cmd": ":one",
+    "columns": [
+      {
+        "name": "mean",
+        "type": {
+          "name": "real",
+          "nullable": true
+        }
+      },
+      {
+        "name": "sum",
+        "type": {
+          "name": "real",
+          "nullable": true
+        }
+      },
+      {
+        "name": "ids",
+        "type": {
+          "name": "integer",
+          "nullable": true
+        }
+      },
+      {
+        "name": "names",
+        "type": {
+          "name": "text",
+          "nullable": true
+        }
+      }
+    ],
+    "params": []
+  },
+  {
+    "name": "ListUsers",
+    "cmd": ":many",
+    "columns": [
+      {
+        "name": "id",
+        "type": {
+          "name": "integer"
+        },
+        "table": "users"
+      },
+      {
+        "name": "lname",
+        "type": {
+          "name": "text"
+        }
+      },
+      {
+        "name": "next",
+        "type": {
+          "name": "integer"
+        }
+      }
+    ],
+    "params": [
+      {
+        "number": 1,
+        "column": {
+          "name": "id",
+          "type": {
+            "name": "integer"
+          },
+          "table": "users"
+        }
+      },
+      {
+        "number": 2,
+        "column": {
+          "name": "id",
+          "type": {
+            "name": "integer"
+          },
+          "table": "users"
+        }
+      }
+    ]
+  },
+  {
+    "name": "ListPosts",
+    "cmd": ":many",
+    "columns": [
+      {
+        "name": "id",
+        "type": {
+          "name": "integer"
+        },
+        "table": "posts"
+      },
+      {
+        "name": "title",
+        "type": {
+          "name": "text",
+          "nullable": true
+        },
+        "table": "posts"
+      }
+    ],
+    "params": [
+      {
+        "number": 1,
+        "column": {
+          "name": "",
+          "type": {
+            "name": "integer"
+          }
+        }
+      },
+      {
+        "number": 2,
+        "column": {
+          "name": "",
+          "type": {
+            "name": "integer"
+          }
+        }
+      }
+    ]
+  },
+  {
+    "name": "UserPosts",
+    "cmd": ":many",
+    "columns": [
+      {
+        "name": "name",
+        "type": {
+          "name": "text"
+        },
+        "table": "users"
+      },
+      {
+        "name": "title",
+        "type": {
+          "name": "text",
+          "nullable": true
+        },
+        "table": "posts"
+      },
+      {
+        "name": "created",
+        "type": {
+          "name": "text"
+        },
+        "table": "posts"
+      }
+    ],
+    "params": [
+      {
+        "number": 1,
+        "column": {
+          "name": "",
+          "type": {
+            "name": "text"
+          }
+        }
+      }
+    ]
+  },
+  {
+    "name": "CreatePost",
+    "cmd": ":one",
+    "columns": [
+      {
+        "name": "id",
+        "type": {
+          "name": "integer"
+        },
+        "table": "posts"
+      },
+      {
+        "name": "created",
+        "type": {
+          "name": "text"
+        },
+        "table": "posts"
+      }
+    ],
+    "params": [
+      {
+        "number": 1,
+        "column": {
+          "name": "user_id",
+          "type": {
+            "name": "integer"
+          },
+          "table": "posts"
+        }
+      },
+      {
+        "number": 2,
+        "column": {
+          "name": "title",
+          "type": {
+            "name": "text",
+            "nullable": true
+          },
+          "table": "posts"
+        }
+      }
+    ]
+  }
+]

internal/engine/sqlite/dialect/dialect.json

@@ -7,7 +7,7 @@
     "bool": "boolean"
   },
   "bool": "boolean",
-  "comparison": ["=", "==", "<>", "!=", "<", "<=", ">", ">=", "IS", "IS NOT"],
+  "comparison": ["=", "==", "<>", "!=", "<", "<=", ">", ">=", "IS", "IS NOT", "LIKE", "NOT LIKE", "GLOB", "NOT GLOB", "REGEXP", "NOT REGEXP", "MATCH", "NOT MATCH"],
   "comparison_categories": "BNSDU",
   "arithmetic": ["+", "-", "*", "/", "%"],
   "arithmetic_categories": "N",