diff options
Diffstat (limited to 'lib/pure/parsesql.nim')
| -rw-r--r-- | lib/pure/parsesql.nim | 57 |
1 files changed, 42 insertions, 15 deletions
diff --git a/lib/pure/parsesql.nim b/lib/pure/parsesql.nim index 23d43dfe0..a7c938d01 100644 --- a/lib/pure/parsesql.nim +++ b/lib/pure/parsesql.nim @@ -7,14 +7,17 @@ # distribution, for details about the copyright. # -## The ``parsesql`` module implements a high performance SQL file +## The `parsesql` module implements a high performance SQL file ## parser. It parses PostgreSQL syntax and the SQL ANSI standard. ## ## Unstable API. -import strutils, lexbase +import std/[strutils, lexbase] import std/private/decode_helpers +when defined(nimPreviewSlimSystem): + import std/assertions + # ------------------- scanner ------------------------------------------------- type @@ -57,7 +60,7 @@ const reservedKeywords = @[ # statements - "select", "from", "where", "group", "limit", "having", + "select", "from", "where", "group", "limit", "offset", "having", # functions "count", ] @@ -506,6 +509,7 @@ type nkFromItemPair, nkGroup, nkLimit, + nkOffset, nkHaving, nkOrder, nkJoin, @@ -982,7 +986,7 @@ proc parseInsert(p: var SqlParser): SqlNode = parseParIdentList(p, n) result.add n else: - result.add(nil) + result.add(newNode(nkNone)) if isKeyw(p, "default"): getTok(p) eat(p, "values") @@ -1017,7 +1021,7 @@ proc parseUpdate(p: var SqlParser): SqlNode = if isKeyw(p, "where"): result.add(parseWhere(p)) else: - result.add(nil) + result.add(newNode(nkNone)) proc parseDelete(p: var SqlParser): SqlNode = getTok(p) @@ -1029,7 +1033,7 @@ proc parseDelete(p: var SqlParser): SqlNode = if isKeyw(p, "where"): result.add(parseWhere(p)) else: - result.add(nil) + result.add(newNode(nkNone)) proc parseSelect(p: var SqlParser): SqlNode = getTok(p) @@ -1123,6 +1127,11 @@ proc parseSelect(p: var SqlParser): SqlNode = var l = newNode(nkLimit) l.add(parseExpr(p)) result.add(l) + if isKeyw(p, "offset"): + getTok(p) + var o = newNode(nkOffset) + o.add(parseExpr(p)) + result.add(o) proc parseStmt(p: var SqlParser; parent: SqlNode) = if isKeyw(p, "create"): @@ -1179,9 +1188,12 @@ type proc add(s: var SqlWriter, thing: char) = s.buffer.add(thing) -proc add(s: var SqlWriter, thing: string) = +proc prepareAdd(s: var SqlWriter) {.inline.} = if s.buffer.len > 0 and s.buffer[^1] notin {' ', '\L', '(', '.'}: s.buffer.add(" ") + +proc add(s: var SqlWriter, thing: string) = + s.prepareAdd s.buffer.add(thing) proc addKeyw(s: var SqlWriter, thing: string) = @@ -1223,6 +1235,17 @@ proc addMulti(s: var SqlWriter, n: SqlNode, sep = ',', prefix, suffix: char) = proc quoted(s: string): string = "\"" & replace(s, "\"", "\"\"") & "\"" +func escape(result: var string; s: string) = + result.add('\'') + for c in items(s): + case c + of '\0'..'\31': + result.add("\\x") + result.add(toHex(ord(c), 2)) + of '\'': result.add("''") + else: result.add(c) + result.add('\'') + proc ra(n: SqlNode, s: var SqlWriter) = if n == nil: return case n.kind @@ -1235,7 +1258,8 @@ proc ra(n: SqlNode, s: var SqlWriter) = of nkQuotedIdent: s.add(quoted(n.strVal)) of nkStringLit: - s.add(escape(n.strVal, "'", "'")) + s.prepareAdd + s.buffer.escape(n.strVal) of nkBitStringLit: s.add("b'" & n.strVal & "'") of nkHexStringLit: @@ -1370,6 +1394,9 @@ proc ra(n: SqlNode, s: var SqlWriter) = of nkLimit: s.addKeyw("limit") s.addMulti(n) + of nkOffset: + s.addKeyw("offset") + s.addMulti(n) of nkHaving: s.addKeyw("having") s.addMulti(n) @@ -1436,7 +1463,7 @@ proc ra(n: SqlNode, s: var SqlWriter) = s.addKeyw("enum") rs(n, s) -proc renderSQL*(n: SqlNode, upperCase = false): string = +proc renderSql*(n: SqlNode, upperCase = false): string = ## Converts an SQL abstract syntax tree to its string representation. var s: SqlWriter s.buffer = "" @@ -1445,8 +1472,8 @@ proc renderSQL*(n: SqlNode, upperCase = false): string = return s.buffer proc `$`*(n: SqlNode): string = - ## an alias for `renderSQL`. - renderSQL(n) + ## an alias for `renderSql`. + renderSql(n) proc treeReprAux(s: SqlNode, level: int, result: var string) = result.add('\n') @@ -1464,7 +1491,7 @@ proc treeRepr*(s: SqlNode): string = result = newStringOfCap(128) treeReprAux(s, 0, result) -import streams +import std/streams proc open(L: var SqlLexer, input: Stream, filename: string) = lexbase.open(L, input) @@ -1478,7 +1505,7 @@ proc open(p: var SqlParser, input: Stream, filename: string) = p.tok.literal = "" getTok(p) -proc parseSQL*(input: Stream, filename: string): SqlNode = +proc parseSql*(input: Stream, filename: string): SqlNode = ## parses the SQL from `input` into an AST and returns the AST. ## `filename` is only used for error messages. ## Syntax errors raise an `SqlParseError` exception. @@ -1489,8 +1516,8 @@ proc parseSQL*(input: Stream, filename: string): SqlNode = finally: close(p) -proc parseSQL*(input: string, filename = ""): SqlNode = +proc parseSql*(input: string, filename = ""): SqlNode = ## parses the SQL from `input` into an AST and returns the AST. ## `filename` is only used for error messages. ## Syntax errors raise an `SqlParseError` exception. - parseSQL(newStringStream(input), "") + parseSql(newStringStream(input), "") |