Introducing for blocks

Signed-off-by: Julien Eluard <julien.eluard@gmail.com>

examples/src/pluto/examples.cljs

@@ -38,7 +38,9 @@
   :random)
 
 (defn render [h el]
-  (reagent/render (h {:name "Test Extension"}) el))
+  (reagent/render (h {:name "Test Extension"
+                      :users [{:nm "Jane"}
+                              {:nm "Sue"}]}) el))
 
 (defn errors-list [v]
   (fn []

figwheel/resources/public/assets/extensions/demo/extension.edn

@@ -11,7 +11,7 @@
    [alert {:value "Eh! ${you}"}])
 
  views/main
- (let [{name :name}   properties
+ (let [{name :name users :users}   properties
        {cond? :cond?} [random-boolean]]
    [view
     [button {:on-click [my-alert {:arg name}]}
@@ -20,4 +20,8 @@
       [text {:style {:color "green"}}
        name]
       [text {:style {:color "red"}}
-       name])])}
+       name])
+    [view "Nested for block"]
+    (for [{nm :nm} users]
+      (for [{nm2 :nm} users]
+        [view nm " and " nm2]))])}

src/pluto/reader/blocks.cljc

@@ -13,30 +13,27 @@
   "Parse a block element. Return hiccup data."
   (fn [ctx ext [type]] type))
 
-(defn resolve-binding-value [v]
-  (cond
-    (vector? v) @(re-frame/subscribe v) ;; TODO better abstract query
-    (not (list? v)) v))
-
-(defn resolve-binding-key [k v]
-  (if (symbol? k)
-    k
-    ;; TODO handle errors
-    (:data (destructuring/destructure k v))))
-
 (defn substitute-query-values [m v]
-  (if (vector? v)
-    (walk/prewalk #(or (get m %) %) v)
-    v))
+  (walk/prewalk #(or (get m %) %) v))
 
-(defn assoc-binding
-  [m k v]
-  (let [resolved-value (resolve-binding-value
-                        (substitute-query-values m v))
-        o (resolve-binding-key k resolved-value)]
-    (if (symbol? o)
-      (assoc m o resolved-value)
-      (merge m o))))
+(defn resolve-rhs [env v]
+  (cond
+    (= v 'properties) (get env :pluto.reader/properties)
+    (symbol? v) (get env v)
+    (vector? v) (some-> (re-frame/subscribe (substitute-query-values env v)) deref)
+    :else v))
+
+(defn destructure-into [env k v]
+  (if (map? k)
+    (into env (:data (destructuring/destructure k v)))
+    (assoc env k v)))
+
+(defn resolve-binding [env k v]
+  (let [v' (resolve-rhs env v)]
+    (destructure-into env k v')))
+
+(defn resolve-bindings-into [env bindings]
+  (reduce #(apply resolve-binding %1 %2) (or env {}) (partition 2 bindings)))
 
 (defn replace-atom [values o]
   (cond (contains? values o) (get values o)
@@ -56,23 +53,24 @@
             (coll? res) (into (empty res) (map f2 res))
             :else res))))
 
-(declare let-block bindings->env)
+(declare let-block for-block)
 
-(defn let-block [{:keys [prev-env ctx ext bindings env]} children]
-  ;; env here is always a destructured set of properties
-  (let [env' (merge env prev-env)
-        {:keys [data errors]} (bindings->env env' ctx ext bindings)
-        ;; this can be moved to into bindings->env now
-        
-        values (reduce-kv assoc-binding env' data)]
-    (walkup-upto-leaf #(replace-atom values %)
-                      #(and (vector? %) (= let-block (first %)))
-                      (fn [[_ props children]]
-                        [let-block (assoc props :prev-env values) children])
+(defn let-block [{:keys [prev-env bindings]} children]
+  (let [new-env (resolve-bindings-into prev-env bindings)]
+    (walkup-upto-leaf #(replace-atom new-env %)
+                      #(and (vector? %) (#{for-block let-block} (first %)))
+                      (fn [[x props children]]
+                        [x (assoc props :prev-env new-env) children])
                       children)))
 
-(defn properties? [o]
-  (= 'properties o))
+(defn for-block [{:keys [wrapper-component prev-env bindings]} children]
+  (let [[k v] bindings
+        for-values (resolve-rhs prev-env v)]
+    (when (sequential? for-values)
+      (into [wrapper-component {}]
+            (for [val for-values]
+              (let-block {:prev-env prev-env :bindings [k val]}
+                children))))))
 
 (defn static-value? [v]
   (or (utils/primitive? v) (map? v)))
@@ -84,47 +82,19 @@
   (and (or (symbol? k) (map? k))
        (or (symbol? v) (static-value? v) (query? v))))
 
-(defn- resolve-symbol [m s]
-  (if (and (symbol? s) (not= 'properties s))
-    (resolve-symbol m (get m s))
-    s))
-
-(defn resolve-env
-  "Resolve key/value pairs, specifically:
-   * 'properties are kept as is
-   * symbol values are replaced by their respective values if already present in the let scope
-   * queries (defined as vectors) are replaced by atoms
-
-   Returns a map of:
-   * :data the resolved values
-   * :errors the errors"
-  [ctx ext {:keys [data] :as m} k v]
-  ;; TODO Do not duplicate checks
-  (if (valid-bindings? k v)
-    (cond
-      (properties? v) (assoc-in m [:data 'properties] k)
-      (static-value? v)
-      (if (map? k)
-        (if-let [o (destructuring/destructure k v)]
-          (errors/merge-results m o)
-          {:errors [(errors/error ::errors/invalid-destructuring-format [k v])]})
-        (assoc-in m [:data k] v))
-      (query? v)
-      (let [{:keys [data errors]} (types/resolve ctx ext :query v)]
-        (errors/merge-errors (assoc-in m [:data k] data) errors)))
-    {:errors [(errors/error ::errors/invalid-bindings [k v])]}))
-
 (defn- valid-bindings-form? [bindings]
   (even? (count bindings)))
 
-;; errors are a problem here we shouldn't be returning data errors anymore
-(defn bindings->env [prev-env ctx ext bindings]
-  (doall
-   (reduce (fn [accum [k v]]
-             (resolve-env ctx ext accum k
-                          (resolve-symbol (:data accum) v)))
-           {:data prev-env}
-           (partition 2 bindings))))
+(defn resolve-and-validate-queries [ctx ext bindings]
+  (reduce (fn [accum [k v]]
+            (if (vector? v)
+              (let [{:keys [data errors]} (types/resolve ctx ext :query v)]
+                (if (not-empty errors)
+                  (update accum :errors concat errors)
+                  (update accum :data concat [k data])))
+              (update accum :data concat [k v])))
+          {:data []}
+          (partition 2 bindings)))
 
 ;; we also need a set of available symbols bound at this point
 (defn validate-bindings [bindings]
@@ -139,31 +109,39 @@
              (map first)
              (filter (some-fn sequential? map?))
              (mapcat destructuring/validate-destructure-bindings)))))
-
     [(errors/error ::errors/invalid-bindings-format bindings)]))
 
-;; shouldn't need to do this really should inject props
-;; into the initial map from the top
-(defn prop-env-from-bindings [bindings]
-  (some->> bindings
-           (partition 2)
-           (filter #(= (second %) 'properties))
-           first
-           reverse
-           (apply hash-map)))
-
 (defmethod parse 'let [ctx ext [_ bindings & body]]
-  (if-let [errors (validate-bindings bindings)]
-    {:errors errors}
-    ;; TODO fail if some symbol are not defined in the env
-    (if (= 1 (count body))
-      (let [prop-env (prop-env-from-bindings bindings)]
-        {:data [let-block (cond-> {:ctx ctx
-                                   :ext ext
-                                   :bindings bindings}
-                            prop-env (assoc :env prop-env))
-                (last body)]})
-      {:errors [(errors/error ::errors/invalid-let-body {:value body})]})))
+  ;; TODO fail if some symbol are not defined in the env
+  (if (not= 1 (count body))
+    {:errors [(errors/error ::errors/invalid-let-body {:value body})]}
+    (let [binding-errors (validate-bindings bindings)]
+      (if (not-empty binding-errors)
+        {:errors binding-errors}
+        (let [{:keys [errors data]} (resolve-and-validate-queries ctx ext bindings)]
+          (if (not-empty errors)
+            {:errors errors}
+            {:data [let-block {:bindings data} (last body)]}))))))
+
+(defmethod parse 'for [ctx ext [_ binding & body]]
+  (cond
+    (not= 1 (count body))
+    {:errors [(errors/error ::errors/invalid-for-body body)]}
+    (or (not= 2 (count binding))
+        (not ((some-fn symbol? map?) (first binding))))
+    {:errors [(errors/error ::errors/invalid-for-binding binding)]}
+    :else
+    (let [wrapper-component (get-in ctx [:capacities :components 'view :value])
+          {:keys [errors data] :as result} (resolve-and-validate-queries ctx ext binding)
+          errors (cond-> errors
+                   (nil? wrapper-component)
+                   (conj errors (errors/error ::errors/unknown-component 'wrapper-component)))]
+      (if (not-empty errors)
+        {:errors errors}
+        (let [binding' data]
+          {:data [for-block {:bindings data
+                             :wrapper-component wrapper-component}
+                  (last body)]})))))
 
 (defn when-block [{:keys [test]} body]
   (when test body))

src/pluto/reader/errors.cljc

@@ -15,6 +15,8 @@
                    ::invalid-reference
                    ::invalid-destructuring-format
                    ::invalid-let-body
+                   ::invalid-for-body
+                   ::invalid-for-binding                  
                    ::invalid-bindings
                    ::invalid-bindings-format
                    ::missing-property

src/pluto/reader/views.cljc

@@ -132,24 +132,15 @@
        errors))
     (parse-hiccup-element ctx ext o)))
 
-(defn- inject-properties [m properties]
-  (if-let [ps (get-in m [:env 'properties])]
-    (let [{:keys [data errors]} (destructuring/destructure ps properties)]
-      (errors/merge-errors
-        {:data
-         (-> m
-             (update :env dissoc 'properties)
-             (update :env merge data))}
-        errors))
-    {:data m}))
-
 (defn- hiccup-with-properties [h properties]
   (if (vector? h)
     (let [[tag & properties-children] h
           [props children]            (resolve-properties-children properties-children)
-          {:keys [data]}              (when properties
-                                        (inject-properties props properties))]
-      (apply conj (if data [tag data] [tag])
+          ;; really only need to add this to the first let block but no harm really
+          props (if (and properties (= tag blocks/let-block))
+                  (assoc-in props [:prev-env :pluto.reader/properties] properties)
+                  props)]
+      (apply conj (if props [tag props] [tag])
              (map #(hiccup-with-properties % properties) children)))
     h))
 

test/pluto/reader/block_test.cljc

@@ -3,25 +3,19 @@
             [pluto.reader :as reader]            
             [pluto.reader.errors :as errors]
             [pluto.reader.blocks :as blocks]
-            [re-frame.core :as re-frame]))
-
-(deftest bindings->env
-  (is (= {:data '{a 1}} (blocks/bindings->env {} {} {} '[a 1])))
-  (is (= (blocks/validate-bindings '[a 1 2])
-         [(errors/error ::errors/invalid-bindings-format '[a 1 2])]))
-  (is (= (blocks/validate-bindings [1 2])
-         [(errors/error ::errors/invalid-bindings [1 2])]))
-  (is (= {:data '{x 1}} (blocks/bindings->env {} {} {} '[{x :x} {:x 1}]))))
+            [re-frame.core :as re-frame])
+  #?(:cljs (:require-macros
+            [pluto.reader.block-test :refer [with-fetch-data]])))
 
 (deftest let-block
   (testing "parse"
-    (is (= {:data [blocks/let-block '{:ctx {}, :ext {}, :bindings [s "Hello"]} 's]}
+    (is (= {:data [blocks/let-block '{:bindings [s "Hello"]} 's]}
            (blocks/parse {} {} '(let [s "Hello"] s))))
     (is (empty?
           (:errors (blocks/parse {:capacities {:queries {'aa {:value :a}}}} {} '(let [{a :a} [aa]] a)))))
 
     (is (= {:data [blocks/let-block
-                   '{:ctx {}, :ext {}, :bindings [{a :a} {:a {:b 1}} {b :b} a]}
+                   '{:bindings [{a :a} {:a {:b 1}} {b :b} a]}
                    'b]}
            (blocks/parse {} {} '(let [{a :a} {:a {:b 1}} {b :b} a] b))))
     (is (empty?
@@ -29,7 +23,8 @@
                                  {:queries {'aa {:value :a :arguments {:x :string}}}}}
                                 {}
                                 '(let [x 1 {a :a} [aa {:x x}]] a)))))
-    (is (= {:data [blocks/let-block '{:ctx {}, :ext {}, :bindings [s "Hello"]}
+    
+    (is (= {:data [blocks/let-block '{:bindings [s "Hello"]}
                    ['test {} 's]]}
            (blocks/parse {} {} (list 'let ['s "Hello"] ['test {} 's]))))
     (is (= (blocks/validate-bindings '[s "Hello" 1])
@@ -41,7 +36,7 @@
   (is (= {:errors [(errors/error ::errors/invalid-bindings-format ['s "Hello" 1])]}
          (blocks/parse {} {} (list 'let ['s "Hello" 1] ['test {} 's]))))
   
-  (is (= {:data [blocks/let-block '{:ctx {}, :ext {}, :bindings [{a :a} {:a 1}]}
+  (is (= {:data [blocks/let-block '{:bindings [{a :a} {:a 1}]}
                  '[test {} a]]}
          (blocks/parse {} {} '(let [{a :a} {:a 1}] [test {} a]))))
 
@@ -67,6 +62,50 @@
   (is (= (first-error-type (blocks/parse {} {} '(when asdf)))
          :pluto.reader.errors/invalid-when-block)))
 
+(declare let-test-capacities)
+
+(deftest resolve-bindings
+  (is (= '{a "asdf"
+           b "asdf"}
+         (blocks/resolve-binding '{a "asdf"} 'b 'a)))
+  (is (= '{a {:asdf "foo"}, asdf "foo"}
+         (blocks/resolve-binding '{a {:asdf "foo"}} '{asdf :asdf} 'a)))
+  (is (= '{:pluto.reader/properties {:asdf "foo"}, asdf "foo"}
+         (blocks/resolve-binding
+          '{:pluto.reader/properties {:asdf "foo"}} '{asdf :asdf} 'properties)))
+  (is (= "asdfg"
+         (blocks/resolve-rhs {} '[::identity-query {:x "asdfg"}])))
+
+  (is (= "asdfg"
+         (blocks/resolve-rhs '{a "asdfg"} '[::identity-query {:x a}])))
+  
+  (is (= '{a "asdf", b "asdf", c "asdf" :hey 1}
+         (blocks/resolve-bindings-into {:hey 1} '[a "asdf" b a c b])))
+  
+
+  )
+
+(deftest resolve-and-validate-queries
+  (is (= {:data
+          '[a [:pluto.reader.block-test/identity-query {:x "asdf"}]
+            g "asdf"
+            b [:pluto.reader.block-test/identity-map {:x "asdf"}]]}
+
+         (blocks/resolve-and-validate-queries
+          {:capacities let-test-capacities} {}
+          '[a [identity-query {:x "asdf"}]
+            g "asdf"
+            b [identity-map   {:x "asdf"}]])))
+
+  (is (not-empty (:errors (blocks/resolve-and-validate-queries
+        {:capacities let-test-capacities} {}
+        '[a [identity-querye {:x "asdf"}]]))))
+  
+  (is (empty? (:errors (blocks/resolve-and-validate-queries
+                        {:capacities let-test-capacities} {}
+                        '[a [identity-query {:x a}]]))))
+  
+  )
 
 ;; The following is all set up so that we can fake "render" the blocks
 ;; in the resulting view tree
@@ -80,9 +119,26 @@
 (re-frame/reg-sub ::identity-query
                   (fn [db [_ {:keys [x]}]] x))
 
+(re-frame/reg-sub ::bool-query
+                  (fn [db [_ {:keys [x]}]] (= x "true")))
+
+(re-frame/reg-sub ::array-query
+                  (fn [db [_ {:keys [x y]}]] (cond-> []
+                                               x (conj x)
+                                               y (conj y))))
+
 (re-frame/reg-sub ::identity-map
                   (fn [db [_ {:keys [x]}]] {:asdf x}))
 
+(def fetch-data (atom {}))
+
+(re-frame/reg-sub ::fetch-data
+                  (fn [db [_ {:keys [id]}]] (get @fetch-data id)))
+
+#?(:clj (defmacro with-fetch-data [data & body]
+          `(do (swap! fetch-data merge ~data)
+               ~@body)))
+
 (def let-test-capacities
   {:components {'view   {:properties {}
                          :value      view-component}
@@ -91,7 +147,10 @@
                 'text   {:properties {}
                          :value      text-component}}
    :queries '{identity-query {:value ::identity-query :arguments {:x :string}}
-              identity-map {:value ::identity-map :arguments {:x :string}}}
+              identity-map   {:value ::identity-map :arguments {:x :string}}
+              bool-query     {:value ::bool-query :arguments {:x :string}}
+              fetch-data     {:value ::fetch-data :arguments {:id :string}}
+              array-query    {:value ::array-query :arguments {:x :string :y :string}}}
    :events {'alert
             {:value :alert}}
    :hooks {:main
@@ -109,23 +168,36 @@
   (-> (reader/parse {:capacities let-test-capacities} extention)
       exec))
 
-(defn simple-render-tree-blocks [[x & xs]]
+(defn valid-input [val]
+  (or (seq? val)
+      (nil? val)
+      (map? val)
+      (vector? val)
+      (symbol? val)
+      (string? val)
+      (number? val)))
+
+; vector-tag | list-of-vector-tags => list-of-vector-tags
+(defn simple-render-tree-blocks [current]
+  {:pre [(valid-input current)]
+   :post [(or (seq? %) (nil? %))]}
   (cond
-    (and (fn? x) (#{pluto.reader.blocks/if-block
-                    pluto.reader.blocks/when-block
-                    pluto.reader.blocks/let-block} x))
-    (let [new-tree (apply x xs)]
-      (if (sequential? new-tree)
-        (simple-render-tree-blocks new-tree)
-        new-tree))
-    :else 
-    (apply
-     vector
-     x
-     (map #(if (sequential? %)
-             (simple-render-tree-blocks %)
-             %)
-          xs))))
+    (seq? current)
+    (mapcat simple-render-tree-blocks current)
+    (vector? current)
+    (let [[x & xs] current]
+      (cond
+        (and (fn? x) (#{pluto.reader.blocks/if-block
+                        pluto.reader.blocks/when-block
+                        pluto.reader.blocks/let-block
+                        pluto.reader.blocks/for-block
+                        } x))
+        (let [new-tree (apply x xs)]
+          (simple-render-tree-blocks new-tree))
+        :else 
+        (list (apply vector x (mapcat simple-render-tree-blocks xs)))))
+    (nil? current) current
+    :else (list current)))
 
 (defn blocks-render [block-syn]
   (let [{:keys [execed errors] :as res}
@@ -147,116 +219,176 @@
 
 (deftest if-when-block-rendering
   ;; need to set up a query to have a false value?
-  (is (= [view-component "true"]
+  (is (= [[view-component "true"]]
          (blocks-render '(let [a "asdf"]
                            (if a
                              [view "true"]
                              [view "false"])))))
   
-    (is (= [view-component "false"]
-           (blocks-render '(let [a [identity-query {:x false}]]
-                             (if a
-                               [view "true"]
-                               [view "false"])))))
-  (is (= [view-component "true"]
+  (is (= [[view-component "false"]]
+       (blocks-render '(let [a [bool-query {:x "false"}]]
+                         (if a
+                           [view "true"]
+                           [view "false"])))))
+
+  (is (= [[view-component "true"]]
+         (blocks-render '(let [a [bool-query {:x "true"}]]
+                           (if a
+                             [view "true"]
+                             [view "false"])))))
+  
+  (is (= [[view-component "true"]]
          (blocks-render '(let [a "asdf"]
                            (when a [view "true"])))))
-  
-  (is (= [view-component nil]
-         (blocks-render '(let [a [identity-query {:x false}]]
+
+  (is (= [[view-component]]
+         (blocks-render '(let [a [bool-query {:x "false"}]]
                            [view (when a [view "true"])]))))
+  
   )
 
 (deftest basic-let-block-replacement []
-  (is (= [view-component "hello"]
+  (is (= [[view-component "hello"]]
          (blocks-render '(let [a "hello"]
                            [view a]))))
-  (is (= [view-component "hello" "jenny"
-          [text-component "jenny" "hello"]
-          [text-component "hello" "darlene"]]
+  
+  (is (= [[view-component "hello" "jenny"
+           [text-component "jenny" "hello"]
+           [text-component "hello" "darlene"]]]
          (blocks-render '(let [a "hello"
                                b "jenny"
                                c "darlene"]
                            [view a b
                             [text b a]
                             [text a c]]))))
-  (is (= [view-component "john"]
+  (is (= [[view-component "john"]]
          (blocks-render '(let [a "john"
                                b a]
                            [view b]))))
-  (is (= [view-component "john"]
+  (is (= [[view-component "john"]]
          (blocks-render '(let [a "john"
                                b a]
                            [view b]))))
-  (is (= [view-component "john"]
+  (is (= [[view-component "john"]]
          (blocks-render '(let [a "john"]
                            (let [b a]
                              [view b])))))
-  (is (= [view-component "john"]
+  (is (= [[view-component "john"]]
          (blocks-render '(let [a "john"
                                dd a]
                            (let [b a
                                  c b]
-                             [view b]))))))
+                             [view b])))))
+  )
 
 (deftest let-blocks-with-properties
-  (is (= [view-component "test-name-prop"]
+  (is (= [[view-component "test-name-prop"]]
          (blocks-render '(let [{name :name} properties]
                            [view name]))))
 
-  (is (= [view-component "test-name-prop"]
+  (is (= [[view-component "test-name-prop"]]
          (blocks-render '(let [{name :name} properties
                                b name]
                            [view b]))))
 
-  (is (= [view-component "jolly"]
+  (is (= [[view-component "jolly"]]
          (blocks-render '(let [{name :name} properties
                                b name]
                            (let [name "jolly"]
                              [view name])))))
 
-  ;; doesn't work and should work
-  ;; this is caused by the way that properties are bound
-  ;; seperately
-  #_(is (= [view-component "test-name-prop"]
-           (blocks-render '(let [name "jolly"
-                                 {name :name} properties]
-                             [view name]))
-           ))
-
+  (is (= [[view-component "test-name-prop"]]
+         (blocks-render '(let [name "jolly"
+                               {name :name} properties]
+                           [view name]))))
+  
   )
 
 (deftest let-blocks-with-queries
-  (is (= [view-component "a temp"]
+  (is (= [[view-component "a temp"]]
          (blocks-render '(let [temp [identity-query {:x "a temp"}]]
                            [view temp]))))
 
-  (is (= [view-component "a temp" "a temp"]
+  (is (= [[view-component "a temp" "a temp"]]
          (blocks-render '(let [a "a temp"
                                temp [identity-query {:x a}]]
                            [view a temp]))))
 
-  (is (= [view-component "a temp" "charmed"]
+  (is (= [[view-component "a temp" "charmed"]]
          (blocks-render '(let [a "a temp"
                                {asdf :asdf} [identity-map {:x "charmed"}]]
                            [view a asdf]))))
-  
  
-   ;; this should work as well but ...
-  #_(is (= [view-component "a temp" "a temp"]
-           (blocks-render '(let [a "a temp"
-                                 temp [identity-query {:x a}]
+  (is (= [[view-component "a temp" "a temp"]]
+         (blocks-render '(let [a "a temp"
+                               temp [identity-query {:x a}]
                                  ouch temp]
-                             [view temp ouch]))
-           
-         ))
+                           [view temp ouch]))))
 
-  (is (= [view-component "a temp" "a temp"]
+  (is (= [[view-component "a temp" "a temp"]] 
          (blocks-render '(let [a "a temp"
                                temp [identity-query {:x a}]]
                            (let [ouch temp]
-                               [view temp ouch])))))
+                             [view temp ouch])))))
 
+  (is (= [[view-component "hello"]]
+         (with-fetch-data {"data-id" {:foo "hello"}}
+           (blocks-render '(let [{foo :foo} [fetch-data {:id "data-id"}]]
+                             [view foo])))))
   
   )
 
+(deftest for-block-parse
+  (is (= {:data
+          [blocks/for-block
+           {:bindings '(a [:pluto.reader.block-test/identity-query {:x a}])
+            :wrapper-component view-component}
+           'asdf]}
+         (blocks/parse {:capacities let-test-capacities} {}
+                       '[for [a [identity-query {:x a}]] asdf]))
+      ))
+
+(deftest for-blocks
+  (is (= [[view-component {} [view-component "foo"] [view-component "bar"]]]
+         (blocks-render '(for [a [array-query {:x "foo" :y "bar"}]]
+                           [view a]))))
+
+  (is (= [[view-component {} [view-component "foo"] [view-component "bar"]]]
+         (blocks-render '(let [b "bar"]
+                           (for [a [array-query {:x "foo" :y b}]]
+                             [view a])))))
+
+  (is (= [[view-component {} [view-component "foo"] [view-component "bar"]]]
+         (blocks-render '(let [b "bar"
+                               c [array-query {:x "foo" :y b}]]
+                           (for [a c]
+                             [view a])))))
+  
+  (is (= [[view-component {} [view-component "foo"] [view-component "bar"]]]
+         (blocks-render '(for [a [array-query {:x "foo" :y "bar"}]]
+                           (let [b a]
+                             [view b])))))
+  
+  (with-fetch-data {"for-blocks-data" [{:name "Jane"} {:name "John"} {:name "Sue"}]}
+
+    (is (= [[view-component {}
+             [view-component "Jane"]
+             [view-component "John"]
+             [view-component "Sue"]]]
+           (blocks-render
+            '(for [{name :name} [fetch-data {:id "for-blocks-data"}]]
+               [view name]))))
+
+    (is (= [[view-component {}
+             [view-component "Jane"]
+             [view-component "John"]
+             [view-component "Sue"]]]
+           (blocks-render '(for [{name :name} [fetch-data {:id "for-blocks-data"}]]
+                             (let [b name]
+                               [view b])))))
+    
+    )
+
+  
+  
+  )

test/pluto/reader_test.cljc

@@ -62,12 +62,8 @@
 
 (deftest parse-blocks
   (is (= [blocks/let-block
-          '{:bindings [s "Hello"],
-           :ctx {:capacities {:components {text :text, view :view},
-                              :hooks {:main {:properties {:view :view}}}}},
-           :ext {meta {:description "", :documentation "", :name ""},
-                 hooks/main.a {:view [views/main]},
-                 views/main (let [s "Hello"] [text {} s])}}
+          '{:bindings [s "Hello"]
+            :prev-env {:pluto.reader/properties {}}}
           '[text {} s]]
          (view (reader/parse default-capacities
                              (extension {'views/main   (list 'let ['s "Hello"] ['text {} 's])