tests and new error

docs/dynamic_rules.md

@@ -492,9 +492,7 @@ eval(${"var"});
 
 ##### `@filter`
 
-The `@filter` restriction allows you to restrict the rule by name of matched variable or literal, const or anything else! 
-
-More about which can be captured you can read in [phpgrep doc](https://github.com/VKCOM/noverify/blob/master/src/phpgrep/pattern_language.md#matcher-expressions)
+The `@filter` restriction allows you to restrict the rule by name of matched variable or literal.
 
 Thus, the rule will be applied only if there is a matched variable that matches passed regexp.
 

src/linter/root.go

@@ -1893,7 +1893,14 @@ func (d *rootWalker) runRule(n ir.Node, sc *meta.Scope, rule *rules.Rule) bool {
 		matched = true
 	} else {
 		for _, filterSet := range rule.Filters {
-			if d.checkFilterSet(&m, sc, filterSet) {
+
+			filterMatched, errorFilterSet := d.checkFilterSet(&m, sc, filterSet)
+			if errorFilterSet != nil {
+				d.Report(n, rule.Level, rule.Name, "%s", errorFilterSet)
+				return true
+			}
+
+			if filterMatched {
 				matched = true
 				break
 			}
@@ -1950,7 +1957,7 @@ func (d *rootWalker) checkTypeFilter(wantType *phpdoc.Type, sc *meta.Scope, nn i
 	return rules.TypeIsCompatible(wantType.Expr, haveType.Expr)
 }
 
-func (d *rootWalker) checkFilterSet(m *phpgrep.MatchData, sc *meta.Scope, filterSet map[string]rules.Filter) bool {
+func (d *rootWalker) checkFilterSet(m *phpgrep.MatchData, sc *meta.Scope, filterSet map[string]rules.Filter) (bool, error) {
 	// TODO: pass custom types here, so both @type and @pure predicates can use it.
 
 	for name, filter := range filterSet {
@@ -1960,24 +1967,27 @@ func (d *rootWalker) checkFilterSet(m *phpgrep.MatchData, sc *meta.Scope, filter
 		}
 
 		if !d.checkTypeFilter(filter.Type, sc, nn) {
-			return false
+			return false, nil
 		}
 		if filter.Pure && !solver.SideEffectFree(d.scope(), d.ctx.st, nil, nn) {
-			return false
+			return false, nil
 		}
 		if filter.Regexp != nil {
 			switch v := nn.(type) {
 			case *ir.SimpleVar:
 				if !filter.Regexp.MatchString(v.Name) {
-					return false
+					return false, nil
 				}
 			case *ir.String:
 				if !filter.Regexp.MatchString(v.Value) {
-					return false
+					return false, nil
 				}
+			default:
+				// logical paradox: we handled it, but does not support that's why here false
+				return false, fmt.Errorf("applying @filter for construction '%s' does not support. Current supported capturing types are str and var", d.nodeText(nn))
 			}
 		}
 	}
 
-	return true
+	return true, nil
 }

src/tests/rules/rules_test.go

@@ -848,6 +848,40 @@ function testInsecureUrl() {
 	test.RunRulesTest()
 }
 
+func TestFilterStrVarCatching(t *testing.T) {
+	rfile := `<?php
+function catchingDiffTypes() {
+  /**
+   * @warning str '$name' warning
+   * @filter  $name ^str_name$
+   */
+  callFunc(${'name:str'});
+
+  /**
+   * @warning var '$name' warning
+   * @filter  $name ^var_name$
+   */
+  callFunc(${'name:var'});
+
+}
+`
+	test := linttest.NewSuite(t)
+	test.RuleFile = rfile
+	test.AddFile(`<?php
+  // For a string literal: captured without quotes inside the filter
+  callFunc("str_name"); // str '"str_name"' warning
+
+  // For variable: name without dollar sign
+  $var_name = "";
+  callFunc($var_name); // var '$var_name' warning
+`)
+	test.Expect = []string{
+		`str '"str_name"' warning`,
+		`var '$var_name' warning`,
+	}
+	test.RunRulesTest()
+}
+
 func TestFilterMultiCatching(t *testing.T) {
 	rfile := `<?php
 function catchingDiffTypes() {
@@ -904,8 +938,8 @@ function catchingDiffTypes() {
    * @filter  $name ^\$a\+1$
    */
   callFunc(${'name:expr'});
-}
-`
+}`
+
 	test := linttest.NewSuite(t)
 	test.RuleFile = rfile
 	test.AddFile(`<?php
@@ -942,15 +976,16 @@ function catchingDiffTypes() {
 	test.Expect = []string{
 		`str '"str_name"' warning`,
 		`var '$var_name' warning`,
-		"call 'funcNane()' warning",
-		"const 'const_name' warning",
-		"int '42' warning",
-		"float '3.14' warning",
-		"char 'a' warning",
-		`func 'function() {}' warning`,
-		"expr '$a+1' warning",
+		`applying @filter for construction 'funcNane()' does not support. Current supported capturing types are str and var`,
+		`applying @filter for construction 'const_name' does not support. Current supported capturing types are str and var`,
+		`applying @filter for construction '42' does not support. Current supported capturing types are str and var`,
+		`applying @filter for construction '3.14' does not support. Current supported capturing types are str and var`,
+		`char ''a'' warning`,
+		`applying @filter for construction 'function() {}' does not support. Current supported capturing types are str and var`,
+		`applying @filter for construction '$a + 1' does not support. Current supported capturing types are str and var`,
 	}
 	test.RunRulesTest()
+
 }
 
 func TestFilterVariableNoWarning(t *testing.T) {