Expressions: Move GEL into core as expressions (#29072)

* comes from grafana/gel-app * remove transform plugin code * move __expr__ and -100 constants to expr pkg * set OrgID on request plugin context * use gtime for resample duration * in resample, rename "rule" to "window", use gtime for duration, parse duration before exec * remove gel entry from plugins-bundled/external.json which creates an empty array for plugins
2020-11-19 07:17:00 -05:00
parent f01c3f35e1
commit 0cb29d337a
44 changed files with 5770 additions and 401 deletions
@@ -0,0 +1,156 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package parse
+
+import (
+	"fmt"
+	"testing"
+)
+
+// Make the types prettyprint.
+var itemName = map[itemType]string{
+	itemError:      "error",
+	itemEOF:        "EOF",
+	itemNot:        "!",
+	itemAnd:        "&&",
+	itemOr:         "||",
+	itemGreater:    ">",
+	itemLess:       "<",
+	itemGreaterEq:  ">=",
+	itemLessEq:     "<=",
+	itemEq:         "==",
+	itemNotEq:      "!=",
+	itemPlus:       "+",
+	itemMinus:      "-",
+	itemMult:       "*",
+	itemDiv:        "/",
+	itemMod:        "%",
+	itemNumber:     "number",
+	itemComma:      ",",
+	itemLeftParen:  "(",
+	itemRightParen: ")",
+	itemString:     "string",
+	itemFunc:       "func",
+}
+
+func (i itemType) String() string {
+	s := itemName[i]
+	if s == "" {
+		return fmt.Sprintf("item%d", int(i))
+	}
+	return s
+}
+
+type lexTest struct {
+	name  string
+	input string
+	items []item
+}
+
+var (
+	tEOF   = item{itemEOF, 0, ""}
+	tLt    = item{itemLess, 0, "<"}
+	tGt    = item{itemGreater, 0, ">"}
+	tOr    = item{itemOr, 0, "||"}
+	tNot   = item{itemNot, 0, "!"}
+	tAnd   = item{itemAnd, 0, "&&"}
+	tLtEq  = item{itemLessEq, 0, "<="}
+	tGtEq  = item{itemGreaterEq, 0, ">="}
+	tNotEq = item{itemNotEq, 0, "!="}
+	tEq    = item{itemEq, 0, "=="}
+	tPlus  = item{itemPlus, 0, "+"}
+	tMinus = item{itemMinus, 0, "-"}
+	tMult  = item{itemMult, 0, "*"}
+	tDiv   = item{itemDiv, 0, "/"}
+	tMod   = item{itemMod, 0, "%"}
+)
+
+var lexTests = []lexTest{
+	{"empty", "", []item{tEOF}},
+	{"spaces", " \t\n", []item{tEOF}},
+	{"text", `"now is the time"`, []item{{itemString, 0, `"now is the time"`}, tEOF}},
+	{"operators", "! && || < > <= >= == != + - * / %", []item{
+		tNot,
+		tAnd,
+		tOr,
+		tLt,
+		tGt,
+		tLtEq,
+		tGtEq,
+		tEq,
+		tNotEq,
+		tPlus,
+		tMinus,
+		tMult,
+		tDiv,
+		tMod,
+		tEOF,
+	}},
+	{"numbers", "1 02 0x14 7.2 1e3 1.2e-4", []item{
+		{itemNumber, 0, "1"},
+		{itemNumber, 0, "02"},
+		{itemNumber, 0, "0x14"},
+		{itemNumber, 0, "7.2"},
+		{itemNumber, 0, "1e3"},
+		{itemNumber, 0, "1.2e-4"},
+		tEOF,
+	}},
+	{"number plus var", "1 + $A", []item{
+		{itemNumber, 0, "1"},
+		tPlus,
+		{itemVar, 0, "$A"},
+		tEOF,
+	}},
+	// errors
+	{"unclosed quote", "\"", []item{
+		{itemError, 0, "unterminated string"},
+	}},
+	{"single quote", "'single quote is invalid'", []item{
+		{itemError, 0, "invalid character: '"},
+	}},
+	{"invalid var", "$", []item{
+		{itemError, 0, "incomplete variable"},
+	}},
+}
+
+// collect gathers the emitted items into a slice.
+func collect(t *lexTest) (items []item) {
+	l := lex(t.input)
+	for {
+		item := l.nextItem()
+		items = append(items, item)
+		if item.typ == itemEOF || item.typ == itemError {
+			break
+		}
+	}
+	return
+}
+
+func equal(i1, i2 []item, checkPos bool) bool {
+	if len(i1) != len(i2) {
+		return false
+	}
+	for k := range i1 {
+		if i1[k].typ != i2[k].typ {
+			return false
+		}
+		if i1[k].val != i2[k].val {
+			return false
+		}
+		if checkPos && i1[k].pos != i2[k].pos {
+			return false
+		}
+	}
+	return true
+}
+
+func TestLex(t *testing.T) {
+	for i, test := range lexTests {
+		items := collect(&lexTests[i])
+		if !equal(items, test.items, false) {
+			t.Errorf("%s: got\n\t%+v\nexpected\n\t%v", test.name, items, test.items)
+		}
+	}
+}