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checker: error if variable used before declaration

pull/5439/head
joe-conigliaro 2020-06-20 12:42:08 +10:00
parent 1d8d19c977
commit ddd83f1fc6
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GPG Key ID: C12F7136C08206F1
6 changed files with 47 additions and 58 deletions
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42
vlib/v/checker/checker.v
View File

@ -62,20 +62,33 @@ pub fn (mut c Checker) check(ast_file ast.File) {
c.expr_level = 0
c.stmt(stmt)
}
// Check scopes
// TODO
/*
for i, obj in c.file.global_scope.objects {
c.check_scope_vars(c.file.scope)
}
pub fn (mut c Checker) check_scope_vars(sc &ast.Scope) {
for _, obj in sc.objects {
match obj {
ast.Var {
if it.is_mut && !it.is_changed {
c.warn('`$it.name` is declared as mutable, but it was never changed', it.pos)
if !c.pref.is_repl {
if !obj.is_used && obj.name[0] != `_` {
if c.pref.is_prod {
c.error('unused variable: `$obj.name`', obj.pos)
} else {
c.warn('unused variable: `$obj.name`', obj.pos)
}
}
}
// TODO: fix all of these warnings
// if obj.is_mut && !obj.is_changed {
// c.warn('`$obj.name` is declared as mutable, but it was never changed', obj.pos)
// }
}
else {}
}
}
*/
for _, child in sc.children {
c.check_scope_vars(child)
}
}
// not used right now
@ -1917,12 +1930,10 @@ pub fn (mut c Checker) expr(node ast.Expr) table.Type {
ast.ComptimeCall {
node.sym = c.table.get_type_symbol(c.unwrap_generic(c.expr(node.left)))
if node.is_vweb {
x := *c.pref
xx := {
x |
is_vweb: true
} // TODO assoc parser bug
mut c2 := new_checker(c.table, xx)
// TODO assoc parser bug
pref := *c.pref
pref2 := {pref|is_vweb: true}
mut c2 := new_checker(c.table, pref2)
c2.check(node.vweb_tmpl)
c.warnings << c2.warnings
c.errors << c2.errors
@ -2088,6 +2099,11 @@ pub fn (mut c Checker) ident(mut ident ast.Ident) table.Type {
return obj.typ
}
ast.Var {
// incase var was not marked as used yet (vweb tmpl)
obj.is_used = true
if ident.pos.pos < obj.pos.pos {
c.error('undefined variable `$ident.name` (used before declaration)', ident.pos)
}
mut typ := obj.typ
if typ == 0 {
if obj.expr is ast.Ident {

18
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.run.out
View File

@ -1,27 +1,13 @@
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:3:2: warning: unused variable: `b`
1 | fn main() {
2 | a := b
3 | b := c
| ^
4 | c := a
5 | }
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:4:2: warning: unused variable: `c`
2 | a := b
3 | b := c
4 | c := a
| ^
5 | }
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:2:7: error: unresolved variable: `b`
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:2:7: error: undefined variable `b` (used before declaration)
1 | fn main() {
2 | a := b
| ^
3 | b := c
4 | c := a
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:3:7: error: unresolved variable: `c`
vlib/v/checker/tests/run/assign_expr_unresolved_variables_err_chain.v:3:7: error: undefined variable `c` (used before declaration)
1 | fn main() {
2 | a := b
3 | b := c
| ^
4 | c := a
5 | }

6
vlib/v/checker/tests/var_used_before_declaration.out 100644
View File

@ -0,0 +1,6 @@
vlib/v/checker/tests/var_used_before_declaration.v:2:13: error: undefined variable `x` (used before declaration)
1 | fn main() {
2 | println(x)
| ^
3 | x := 'hello v'
4 | }

4
vlib/v/checker/tests/var_used_before_declaration.vv 100644
View File

@ -0,0 +1,4 @@
fn main() {
println(x)
x := 'hello v'
}

12
vlib/v/parser/comptime.v
View File

@ -107,7 +107,7 @@ fn (mut p Parser) vweb() ast.ComptimeCall {
start_pos: 0
parent: p.global_scope
}
file := parse_text(v_code, p.table, p.pref, scope, p.global_scope)
mut file := parse_text(v_code, p.table, p.pref, scope, p.global_scope)
if p.pref.is_verbose {
println('\n\n')
println('>>> vweb template for ${path}:')
@ -115,6 +115,7 @@ fn (mut p Parser) vweb() ast.ComptimeCall {
println('>>> end of vweb template END')
println('\n\n')
}
file = {file| path:html_name}
// copy vars from current fn scope into vweb_tmpl scope
for stmt in file.stmts {
if stmt is ast.FnDecl {
@ -124,12 +125,11 @@ fn (mut p Parser) vweb() ast.ComptimeCall {
for _, obj in p.scope.objects {
if obj is ast.Var {
mut v := obj as ast.Var
v.pos = fn_decl.body_pos
tmpl_scope.register(v.name, *v)
// TODO: this is yuck, track idents in parser
// or defer unused var logic to checker
if v_code.contains(v.name) {
v.is_used = true
}
// set the controller action var to used
// if its unused in the template it will warn
v.is_used = true
}
}
break

23
vlib/v/parser/parser.v
View File

@ -275,29 +275,6 @@ pub fn (mut p Parser) open_scope() {
}
pub fn (mut p Parser) close_scope() {
// TODO move this to checker since is_changed is set there?
if !p.pref.is_repl && !p.scanner.is_fmt {
for _, obj in p.scope.objects {
match obj {
ast.Var {
if !obj.is_used && obj.name[0] != `_` {
if p.pref.is_prod {
p.error_with_pos('unused variable: `$obj.name`', obj.pos)
} else {
p.warn_with_pos('unused variable: `$obj.name`', obj.pos)
}
}
/*
if it.is_mut && !it.is_changed {
p.warn_with_pos('`$it.name` is declared as mutable, but it was never changed',
it.pos)
}
*/
}
else {}
}
}
}
p.scope.end_pos = p.tok.pos
p.scope.parent.children << p.scope
p.scope = p.scope.parent