Create rule S6979

rules/S6979/metadata.json

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+{
+}

rules/S6979/python/metadata.json

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+{
+  "title": "\"torch.tensor\" should be used instead of \"torch.autograd.Variable\"",
+  "type": "CODE_SMELL",
+  "status": "ready",
+  "remediation": {
+    "func": "Constant\/Issue",
+    "constantCost": "2min"
+  },
+  "tags": [
+  ],
+  "defaultSeverity": "Major",
+  "ruleSpecification": "RSPEC-6979",
+  "sqKey": "S6979",
+  "scope": "All",
+  "defaultQualityProfiles": ["Sonar way"],
+  "quickfix": "targeted",
+  "code": {
+    "impacts": {
+      "MAINTAINABILITY": "MEDIUM"
+    },
+    "attribute": "CONVENTIONAL"
+  }
+}

rules/S6979/python/rule.adoc

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+This rule raises when a `torch.autograd.Variable` is instantiated.
+
+== Why is this an issue?
+
+The Pytorch Variable API has been deprecated. The behavior of Variables is now provided by the Pytorch tensors and can be controlled with the `requires_grad` parameter. 
+
+The Variable API now returns tensors anyway, so there should not be any breaking changes.
+
+== How to fix it
+
+Replace the call to `torch.autograd.Variable` with a call to `torch.tensor` and set the `requires_grad` attribute to `True` if needed.
+
+=== Code examples
+
+==== Noncompliant code example
+
+[source,python,diff-id=1,diff-type=noncompliant]
+----
+import torch
+
+x = torch.autograd.Variable(torch.tensor([1.0]), requires_grad=True) # Noncompliant
+x2 = torch.autograd.Variable(torch.tensor([1.0])) # Noncompliant
+----
+
+==== Compliant solution
+
+[source,python,diff-id=1,diff-type=compliant]
+----
+import torch
+
+x = torch.tensor([1.0], requires_grad=True)
+x2 = torch.tensor([1.0])
+----
+
+
+== Resources
+=== Documentation
+
+* Pytorch documentation - https://pytorch.org/docs/stable/autograd.html#variable-deprecated[Variable API]
+
+
+ifdef::env-github,rspecator-view[]
+
+(visible only on this page)
+
+== Implementation specification 
+
+Should be pretty straighforward to implement.
+
+=== Message 
+
+Primary : Replace this call with a call to "torch.tensor".
+
+
+=== Issue location
+
+Primary : Name of the function call
+
+=== Quickfix
+
+Might be tricky to know how to call the `torch.tensor` function.
+If there is an import like `from torch import tensor`, then replace with `tensor(...)`
+If not, then replace with `torch.tensor(...)`
+
+
+endif::env-github,rspecator-view[]