func toSpannerTypeInternal()

in sources/postgres/toddl.go [65:208]
140 lines of code
41 McCabe index (conditional complexity)

func toSpannerTypeInternal(srcType schema.Type, spType string) (ddl.Type, []internal.SchemaIssue) {
	switch srcType.Name {
	case "bool", "boolean":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		case ddl.Int64:
			return ddl.Type{Name: ddl.Int64}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Bool}, nil
		}
	case "bigserial":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened, internal.Serial}
		default:
			return ddl.Type{Name: ddl.Int64}, []internal.SchemaIssue{internal.Serial}
		}
	case "bpchar", "character": // Note: Postgres internal name for char is bpchar (aka blank padded char).
		switch spType {
		case ddl.Bytes:
			if len(srcType.Mods) > 0 {
				return ddl.Type{Name: ddl.Bytes, Len: srcType.Mods[0]}, nil
			}
			return ddl.Type{Name: ddl.Bytes, Len: 1}, nil
		default:
			if len(srcType.Mods) > 0 {
				return ddl.Type{Name: ddl.String, Len: srcType.Mods[0]}, nil
			}
			// Note: bpchar without length specifier is equivalent to bpchar(1)
			return ddl.Type{Name: ddl.String, Len: 1}, nil
		}
	case "bytea":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, nil
		default:
			return ddl.Type{Name: ddl.Bytes, Len: ddl.MaxLength}, nil
		}
	case "date":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Date}, nil
		}
	case "float8", "double precision":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Float64}, nil
		}
	case "float4", "real":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		case ddl.Float64:
			return ddl.Type{Name: ddl.Float64}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Float32}, nil
		}
	case "int8", "bigint":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Int64}, nil
		}
	case "int4", "integer":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Int64}, []internal.SchemaIssue{internal.Widened}
		}
	case "int2", "smallint":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Int64}, []internal.SchemaIssue{internal.Widened}
		}
	case "numeric":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			// TODO: check mod[0] and mod[1] and generate a warning
			// if this numeric won't fit in Spanner's NUMERIC.
			return ddl.Type{Name: ddl.Numeric}, nil
		}
	case "serial":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened, internal.Serial}
		default:
			return ddl.Type{Name: ddl.Int64}, []internal.SchemaIssue{internal.Serial}
		}
	case "text":
		switch spType {
		case ddl.Bytes:
			return ddl.Type{Name: ddl.Bytes, Len: ddl.MaxLength}, nil
		default:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, nil
		}
	case "timestamptz", "timestamp with time zone":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Timestamp}, nil
		}
	case "timestamp", "timestamp without time zone":
		// Map timestamp without timezone to Spanner timestamp.
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.Widened}
		default:
			return ddl.Type{Name: ddl.Timestamp}, []internal.SchemaIssue{internal.Timestamp}
		}
	case "json", "jsonb":
		switch spType {
		case ddl.String:
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, nil
		default:
			return ddl.Type{Name: ddl.JSON}, nil
		}
	case "varchar", "character varying":
		switch spType {
		case ddl.Bytes:
			if len(srcType.Mods) > 0 {
				return ddl.Type{Name: ddl.Bytes, Len: srcType.Mods[0]}, nil
			}
			return ddl.Type{Name: ddl.Bytes, Len: ddl.MaxLength}, nil
		default:
			if len(srcType.Mods) > 0 {
				return ddl.Type{Name: ddl.String, Len: srcType.Mods[0]}, nil
			}
			return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, nil
		}
	}
	return ddl.Type{Name: ddl.String, Len: ddl.MaxLength}, []internal.SchemaIssue{internal.NoGoodType}
}