diag `missing-return`

11 files changed, 104 insertions, 14 deletions

diff --git a/script/config/config.lua b/script/config/config.lua
index df998990..fb72e7c9 100644
--- a/script/config/config.lua
+++ b/script/config/config.lua
@@ -38,7 +38,7 @@ local function getScope(uri, key)
         end
     end
     if uri then
-        ---@type scope
+        ---@type scope?
         local scp = scope.getFolder(uri) or scope.getLinkedScope(uri)
         if scp then
             if not key
diff --git a/script/core/completion/completion.lua b/script/core/completion/completion.lua
index 6b63809e..c9359e9a 100644
--- a/script/core/completion/completion.lua
+++ b/script/core/completion/completion.lua
@@ -1133,7 +1133,6 @@ local function cleanEnums(enums, source)
     return enums
 end
 
----@return boolean
 local function insertEnum(state, src, enums, isInArray)
     if src.type == 'doc.type.string'
     or src.type == 'doc.type.integer'
diff --git a/script/core/diagnostics/missing-return.lua b/script/core/diagnostics/missing-return.lua
new file mode 100644
index 00000000..08932c83
--- /dev/null
+++ b/script/core/diagnostics/missing-return.lua
@@ -0,0 +1,84 @@
+local files  = require 'files'
+local guide  = require 'parser.guide'
+local vm     = require 'vm'
+local lang   = require 'language'
+
+---@param uri uri
+---@param func parser.object
+local function hasDocReturn(uri, func)
+    if not func.bindDocs then
+        return false
+    end
+    for _, doc in ipairs(func.bindDocs) do
+        if doc.type == 'doc.return' then
+            -- don't need return with only one `any`
+            local lastReturn = doc.returns[#doc.returns]
+            if lastReturn.returnIndex ~= 1
+            or vm.getInfer(lastReturn):view(uri) ~= 'any' then
+                return true
+            end
+        end
+    end
+    return false
+end
+
+---@param block parser.object
+---@return boolean
+local function hasReturn(block)
+    if block.hasReturn or block.hasError then
+        return true
+    end
+    if block.type == 'if' then
+        local hasElse
+        for _, subBlock in ipairs(block) do
+            if not hasReturn(subBlock) then
+                return false
+            end
+            if subBlock.type == 'elseblock' then
+                hasElse = true
+            end
+        end
+        return hasElse == true
+    else
+        if block.type == 'while' then
+            if vm.testCondition(block.filter) then
+                return true
+            end
+        end
+        for _, action in ipairs(block) do
+            if guide.isBlockType(action) then
+                if hasReturn(action) then
+                    return true
+                end
+            end
+        end
+    end
+    return false
+end
+
+return function (uri, callback)
+    local state = files.getState(uri)
+    if not state then
+        return
+    end
+
+    guide.eachSourceType(state.ast, 'function', function (source)
+        -- check declare only
+        if #source == 0 then
+            return
+        end
+        if not hasDocReturn(uri, source) then
+            return
+        end
+        if hasReturn(source) then
+            return
+        end
+        local lastAction = source[#source]
+        local finish = lastAction.range or lastAction.finish
+        callback {
+            start   = finish,
+            finish  = finish,
+            message = lang.script('DIAG_MISSING_RETURN'),
+        }
+    end)
+end
diff --git a/script/lclient.lua b/script/lclient.lua
index 680012db..e1504e61 100644
--- a/script/lclient.lua
+++ b/script/lclient.lua
@@ -80,7 +80,6 @@ function mt:reportHangs()
 end
 
 ---@param callback async fun(client: languageClient)
----@return languageClient
 function mt:start(callback)
     CLI = true
 
diff --git a/script/parser/compile.lua b/script/parser/compile.lua
index 83153614..8c5979f7 100644
--- a/script/parser/compile.lua
+++ b/script/parser/compile.lua
@@ -2833,7 +2833,8 @@ local function compileExpAsAction(exp)
                 local block = Chunk[i]
                 if block.type == 'ifblock'
                 or block.type == 'elseifblock'
-                or block.type == 'else' then
+                or block.type == 'elseblock'
+                or block.type == 'function' then
                     block.hasError = true
                     break
                 end
@@ -2986,7 +2987,8 @@ local function parseReturn()
         local block = Chunk[i]
         if block.type == 'ifblock'
         or block.type == 'elseifblock'
-        or block.type == 'else' then
+        or block.type == 'elseblock'
+        or block.type == 'function' then
             block.hasReturn = true
             break
         end
diff --git a/script/parser/guide.lua b/script/parser/guide.lua
index 1ba28d4d..83c84964 100644
--- a/script/parser/guide.lua
+++ b/script/parser/guide.lua
@@ -1276,4 +1276,10 @@ function m.isBasicType(str)
     return basicTypeMap[str] == true
 end
 
+---@param source parser.object
+---@return boolean
+function m.isBlockType(source)
+    return blockTypes[source.type] == true
+end
+
 return m
diff --git a/script/proto/diagnostic.lua b/script/proto/diagnostic.lua
index e449d864..25f187db 100644
--- a/script/proto/diagnostic.lua
+++ b/script/proto/diagnostic.lua
@@ -60,6 +60,7 @@ m.register {
     'missing-parameter',
     'missing-return-value',
     'redundant-return-value',
+    'missing-return',
 } {
     group    = 'unbalanced',
     severity = 'Warning',
diff --git a/script/pub/pub.lua b/script/pub/pub.lua
index 47591ee6..1e9b6c8f 100644
--- a/script/pub/pub.lua
+++ b/script/pub/pub.lua
@@ -136,8 +136,6 @@ function m.task(name, params, callback)
 end
 
 --- 接收反馈
---- 返回接收到的反馈数量
----@return integer
 function m.recieve(block)
     if block then
         local id, name, result = waiter:bpop()
diff --git a/script/vm/compiler.lua b/script/vm/compiler.lua
index b2cdb1be..f42a4768 100644
--- a/script/vm/compiler.lua
+++ b/script/vm/compiler.lua
@@ -492,6 +492,7 @@ function vm.getReturnOfFunction(func, index)
         end
         return vm.createGeneric(rtn, sign)
     end
+    return nil
 end
 
 ---@return vm.node
@@ -976,7 +977,6 @@ local function compileForVars(source)
 end
 
 ---@param source parser.object
----@return vm.node
 local function compileLocal(source)
     vm.setNode(source, source)
 
@@ -1077,7 +1077,7 @@ local binarySwich = util.switch()
     : call(function (source)
         local node1 = vm.compileNode(source[1])
         local node2 = vm.compileNode(source[2])
-        local r1 = vm.test(source[1])
+        local r1 = vm.testCondition(source[1])
         if r1 == true then
             vm.setNode(source, node2)
         elseif r1 == false then
@@ -1090,7 +1090,7 @@ local binarySwich = util.switch()
     : call(function (source)
         local node1 = vm.compileNode(source[1])
         local node2 = vm.compileNode(source[2])
-        local r1 = vm.test(source[1])
+        local r1 = vm.testCondition(source[1])
         if r1 == true then
             vm.setNode(source, node1)
         elseif r1 == false then
@@ -1784,7 +1784,7 @@ local compilerSwitch = util.switch()
             return
         end
         if source.op.type == 'not' then
-            local result = vm.test(source[1])
+            local result = vm.testCondition(source[1])
             if result == nil then
                 vm.setNode(source, vm.declareGlobal('type', 'boolean'))
                 return
diff --git a/script/vm/value.lua b/script/vm/value.lua
index 0ebf5d08..d826d908 100644
--- a/script/vm/value.lua
+++ b/script/vm/value.lua
@@ -4,7 +4,7 @@ local vm       = require 'vm.vm'
 
 ---@param source parser.object?
 ---@return boolean|nil
-function vm.test(source)
+function vm.testCondition(source)
     if not source then
         return nil
     end
diff --git a/script/workspace/scope.lua b/script/workspace/scope.lua
index a0f4fbf7..85053612 100644
--- a/script/workspace/scope.lua
+++ b/script/workspace/scope.lua
@@ -164,7 +164,7 @@ function m.createFolder(uri)
 end
 
 ---@param uri uri
----@return scope
+---@return scope?
 function m.getFolder(uri)
     for _, scope in ipairs(m.folders) do
         if scope:isChildUri(uri) then
@@ -175,7 +175,7 @@ function m.getFolder(uri)
 end
 
 ---@param uri uri
----@return scope
+---@return scope?
 function m.getLinkedScope(uri)
     if m.override and m.override:isLinkedUri(uri) then
         return m.override
@@ -188,6 +188,7 @@ function m.getLinkedScope(uri)
     if m.fallback:isLinkedUri(uri) then
         return m.fallback
     end
+    return nil
 end
 
 ---@param uri uri